JP4883688B2 - Vacuum package, electronic device, and manufacturing method of vacuum package - Google Patents

Description

  The present invention relates to a vacuum package having a sealed chamber formed between a semiconductor substrate such as a silicon substrate and a lid substrate such as a glass substrate, and a feedthrough portion that electrically connects the sealed chamber and the outside. An electronic device having a vacuum package and a method for manufacturing the vacuum package are provided.

  Conventionally, as represented by a mechanical quantity sensor such as an acceleration sensor or an angular velocity sensor, many vacuum packages are provided in which a sensor unit is housed in a sealed chamber maintained in a vacuum atmosphere having a pressure lower than atmospheric pressure. This is to prevent a decrease in detection sensitivity due to damping of the sensor unit, to prevent dust from entering from the outside, and to prevent performance characteristics from changing due to changes in environmental conditions such as temperature and humidity. is there. In such a vacuum package, a semiconductor substrate such as a silicon substrate and a lid substrate such as a glass substrate are generally bonded, and a sensor unit is accommodated in a sealed chamber formed between the two substrates.

By the way, various methods are considered as a method for accommodating the sensor unit in a sealed chamber maintained in a vacuum atmosphere, but the following methods are usually used.
That is, first, an exhaust passage for communicating the sealed chamber and the outside is formed in the lid substrate and the semiconductor substrate, and then the lid substrate and the semiconductor substrate are joined by anodic bonding or the like. Next, the sealed chamber is evacuated through the exhaust passage to create a vacuum atmosphere in the sealed chamber. Finally, a thin film is formed on the lid substrate in a vacuum to close the exhaust passage, thereby vacuum-sealing the sealed chamber. As described above, a method of maintaining the sealed chamber in a vacuum atmosphere by finally closing the exhaust passage with a thin film in a vacuum is a method that is frequently used, and is widely known as a simple method. Note that the exhaust passage generally includes an exhaust hole formed in the lid substrate and an exhaust groove formed in the semiconductor substrate and communicating the exhaust hole and the sealed chamber.

  On the other hand, in the vacuum package, in order to function the sensor unit and the like housed in the sealed chamber separately from the exhaust passage, and to electrically connect various electrodes provided in the sealed chamber to the outside, It is necessary to provide a feed-through portion serving as a general passage. The feedthrough portion is configured by filling a conductive material in a through hole (through hole) formed in the lid substrate by plating or the like. This feed-through portion is essential for the vacuum package to function.

By the way, in forming the exhaust passage and the feedthrough portion described above, several methods have been considered regarding the formation method, arrangement, and the like.
For example, Patent Document 1 describes a pair of lid substrates connected to a semiconductor substrate, in which a feedthrough portion is formed on one lid substrate side and an exhaust passage is formed on the other lid substrate side. ing.
Here, this vacuum package will be briefly described with reference to FIG.

FIG. 34 is a view showing a cross section of the vacuum package 80. As shown in FIG. 34, the vacuum package 80 is obtained by bonding a semiconductor substrate 81 such as a silicon substrate and a pair of insulating lid substrates 82, and a sealed chamber 83 is provided between the substrates 81 and 82. Is formed. In the sealed chamber 83, functional parts such as a sensor part (not shown) are accommodated. In the sealed chamber 83, an island 81a that is electrically connected to the functional unit is formed.
In addition, an exhaust hole 84 is formed in one of the two lid substrates 82. The semiconductor substrate 81 is formed with an exhaust groove 85 that allows the exhaust hole 84 and the sealed chamber 83 to communicate with each other. Thus, after the one lid substrate 82 and the semiconductor substrate 81 are joined, the inside of the sealed chamber 83 is communicated with the outside. That is, the exhaust hole 84 and the exhaust groove 85 function as an exhaust passage. In addition, an insulating thin film 86 is formed on the one lid substrate 82 to block part of the exhaust holes 84 and the exhaust grooves 85. Thereby, the inside of the sealed chamber 83 is vacuum-sealed.

  The other lid substrate 82 has a through hole 87 as a through hole at a position facing the island 81a. Further, a feedthrough portion 88 is provided so as to close the through hole 87 and is electrically connected to the island 81a. In other words, the functional unit can be made to function via the feedthrough portion 88.

  When manufacturing the vacuum package 80 configured as described above, the island 81a, the sealed chamber 83, and the exhaust groove 85 are formed in the semiconductor substrate 81, and the exhaust hole 84 is formed in one lid substrate 82, and the other lid is formed. Through holes 87 are respectively formed in the substrate 82. Next, the semiconductor substrate 81 and the pair of lid substrates 82 are bonded by anodic bonding or the like. Next, a feedthrough portion 88 is formed so as to fill the through hole 87 by plating or the like. Next, evacuation is performed using a vacuum chamber or the like, and the sealed chamber 83 is brought into a vacuum atmosphere through an exhaust passage including the exhaust groove 85 and the exhaust hole 84. Then, a thin film 86 is formed on one lid substrate 82 in a vacuum, and the exhaust passage is sealed. As a result, the inside of the sealed chamber 83 is maintained in a vacuum atmosphere, and the vacuum package 80 in which the feedthrough portion 88 is formed can be manufactured.

  In addition to the above-described one, Patent Document 1 also describes a vacuum package 80 in which exhaust holes 84 and through holes 87 are formed in one lid substrate 82. In this case, a metal film is formed as a thin film 86 on one lid substrate 82. In this way, the exhaust hole 84 is closed and the sealed chamber 83 is sealed, and the through hole 87 is closed and the metal film has a function as the feed-through portion 88.

In addition, when the exhaust passage is closed as described above, an insulating thin film or a metal film is not formed, but a sealing member such as solder or glass paste is dropped directly into the through hole, and the exhaust passage is There is also known a method for closing the frame (see, for example, Patent Documents 2 and 3).
In this case, the sealing member is once heated and dissolved in a vacuum to degas, and then the sealing member is further heated and further dissolved to close the exhaust passage.
JP-A-11-351876 Japanese Patent Laid-Open No. 11-340348 JP 2006-116694 A

However, the following problems remain in the conventional method.
That is, among the methods described in Patent Document 1, the method of forming the exhaust passage on one lid substrate 82 side and forming the feedthrough portion 88 on the other lid substrate 82 side is the two lid substrates 82. It is necessary to form the through hole 87 and the exhaust hole 84 respectively. For this reason, the rigidity of the two lid substrates 82 is decreased, and the bonding strength after bonding to the semiconductor substrate 81 is decreased. For this reason, there is a possibility that it will lead to leakage and reduce the degree of vacuum in the sealed chamber 83. Moreover, since it is necessary to form the through-hole 87 and the exhaust hole 84 in the two lid substrates 82, respectively, there has been a disadvantage that the number of steps increases.

  In addition, when the method of consolidating the exhaust holes 84 and the through holes 87 on the one lid substrate 82 side is adopted, the above-mentioned problem can be avoided, but a new inconvenience occurs. . That is, in this case, the exhaust hole 84 is sealed by forming a metal film, but the metal film can be formed only with a film thickness of about several μm because of the film stress. If the film is formed with a film thickness larger than that, film peeling occurs. Therefore, there is a possibility that the exhaust hole 84 cannot be reliably closed and sealed. In addition, since the metal film is not excellent in adhesion, there are cases where the exhaust hole 84 cannot be reliably closed in this respect. In particular, when the through hole 87 and the exhaust hole 84 are formed in the lid substrate 82, there are cases where the inner peripheral surface is inevitably roughened or the edge portion is chipped. Therefore, it is difficult to reliably block the exhaust hole 84 with a metal layer having poor adhesion.

Therefore, it is also considered that after a metal layer is formed once, an insulating film such as TEOS (Tetra Ethyl Ortho Silicate) is further formed on the metal layer by a CVD method excellent in wraparound. Since this insulating film can be formed to several tens of μm without fear of film peeling, the exhaust hole 84 is reliably sealed by laminating the insulating film on the metal layer. Can do.
However, since the metal film also functions as the feedthrough portion 88, it is necessary to etch the insulating film only within a predetermined range to form a contact hole that exposes the metal layer to the outside. At this time, since the insulating film is formed with a film thickness of several tens of μm in order to ensure the sealing of the through hole 87, it is necessary to etch by the film thickness. However, such deep etching is a very difficult operation in consideration of resist resistance and the like, and cannot be easily realized.
Furthermore, since it is necessary to perform etching in addition to forming the metal film and the insulating film twice, there is a problem that it takes much time and man-hours.

On the other hand, since the methods described in Patent Documents 2 and 3 can seal the exhaust hole pinpoint by using a sealing member, the problem of the metal film can be avoided. When heated, outgas is generated, which may reduce the degree of vacuum in the sealed chamber.
Thus, even if any of the above-described methods is adopted, there are some disadvantages, and it is difficult to manufacture an optimal vacuum package.

  The present invention has been made in view of such circumstances, and its purpose is to easily manufacture without man-hours, and to ensure the feedthrough portion while ensuring the bonding strength between the semiconductor substrate and the lid substrate. Another object of the present invention is to provide a vacuum package with improved performance by improving the degree of vacuum in the sealed chamber, an electronic device having the vacuum package, and a method for manufacturing the vacuum package.

The present invention provides the following means in order to solve the above problems.
The vacuum package manufacturing method according to the present invention includes an insulating first lid substrate and a second lid substrate that are arranged in parallel with each other at a predetermined interval, and a state that is sandwiched between the two lid substrates. A frame portion that is joined in a frame shape, and a column portion that is provided in a sealed chamber surrounded by the frame portion and the first and second lid substrates and has both ends in contact with both lid substrates. A method of manufacturing a vacuum package comprising a semiconductor substrate having a lid substrate forming step of forming exhaust holes and through holes in the first lid substrate, and superimposing the first lid substrate on the semiconductor substrate. A semiconductor substrate forming step of forming an exhaust groove in the semiconductor substrate so as to communicate with the exhaust hole and forming a storage chamber in the semiconductor substrate so as to communicate with the through hole; Only To form the sealed chamber that communicates with the exhaust groove, the frame portion that surrounds the periphery of the sealed chamber, and the support column that is provided in the sealed chamber and has the storage chamber on one end side. Etching and bonding the first lid substrate to one surface of the semiconductor substrate in which the exhaust groove and the storage chamber are formed, and bonding the second lid substrate to the other surface of the semiconductor substrate And a vacuum process for bringing the sealed chamber into a vacuum state via the exhaust groove and the exhaust hole, and insulating the surface of the first lid substrate with a film thickness that closes the exhaust groove in vacuum. A sealing process for forming a film and vacuum-sealing the sealed chamber, and a conductive material is plated so as to fill the storage chamber and the through hole, and one end side is electrically connected to the support column. And the other end is A plating step for forming a feedthrough portion connected to the semiconductor substrate, and forming the storage chamber deeper than the exhaust groove during the semiconductor substrate formation step, so that one of the insulating films is formed during the sealing step. And the insulating film is divided, and the insulating film is divided.

In the manufacturing method of the vacuum package according to the present invention, first, a lid substrate is formed in which an exhaust hole for evacuating the sealed chamber and a through hole that is a through hole of the feedthrough portion are formed in the first lid substrate. Perform the process.
At the same time as or before or after this process, a semiconductor substrate process for forming an exhaust groove and a storage chamber for evacuating the sealed chamber in the semiconductor substrate is performed. At this time, when the first lid substrate and the semiconductor substrate are overlapped, an exhaust groove is formed so as to communicate with the exhaust hole, and a storage chamber is formed so as to communicate with the through hole. Moreover, when forming this storage chamber, it forms so that the depth may become deeper than an exhaust groove.

  After the semiconductor substrate forming step, an etching step is performed in which the semiconductor substrate is etched only in a predetermined region from the side where the exhaust groove and the storage chamber are not formed to form a frame portion and a column portion. At this time, the space surrounded by the frame portion becomes a sealed chamber when the first lid substrate and the second lid substrate are joined later. In addition, by this step, the exhaust groove formed earlier communicates with the space in the frame portion serving as a sealed chamber. Moreover, it will be in the state provided in this space by which the support | pillar part which has the storage chamber formed previously in the one end side becomes a sealed chamber.

Next, after both the above-described lid substrate forming step and etching step are completed, the first lid substrate is bonded to one surface of the semiconductor substrate in which the exhaust groove and the storage chamber are formed, and the second lid substrate is bonded to the semiconductor. A bonding step of bonding to the other surface of the substrate is performed. Note that only the first lid substrate may be bonded first when performing the etching step. In any case, when the first lid substrate and the second lid substrate are bonded, the bonding process is completed.
By this step, the space surrounded by the frame portion becomes a sealed chamber, and both ends of the column portion provided in the sealed chamber are in contact with the first lid substrate and the second lid substrate. Therefore, the storage chamber formed on one end side of the support column communicates with the through hole. Moreover, the sealed chamber is in a state of communicating with the outside through the exhaust groove and the exhaust hole.

After the joining process, a vacuum process is performed for vacuuming the sealed chamber through the exhaust groove and the exhaust hole. That is, the semiconductor substrate bonded to both lid substrates is put into a vacuum chamber and evacuated. At this time, as described above, the sealed chamber is evacuated because it communicates with the outside through the exhaust groove and the exhaust hole.
And after performing this evacuation for a fixed time, the sealing process of vacuum-sealing a sealed chamber is performed. That is, an insulating film such as TEOS is formed on the surface of the first lid substrate in a vacuum. As a result, the surface of the first lid substrate naturally begins to fall and accumulate in the exhaust groove through the exhaust hole, and also begins to accumulate in the storage chamber through the through hole. In addition, when this process is performed, the insulating film is formed with a film thickness that closes the exhaust groove. As a result, the exhaust groove that communicates between the sealed chamber and the outside is closed, so that the sealed chamber can be vacuum-sealed.

  On the other hand, since the storage chamber is formed deeper than the exhaust groove, unlike the exhaust groove, it is not blocked by the insulating film. In other words, the insulating film is simply separated into the bottom of the storage chamber, and the insulating film is separated. Therefore, the storage chamber and the through hole can be kept in communication with each other.

  After this sealing process is completed, a plating process for forming a feedthrough portion in the through-hole that is a through hole is performed. That is, by performing electroplating or electroless plating, a feed-through portion is formed by growing a conductive material such as copper so as to fill the storage chamber and the through hole. The feed-through portion is a conduction path in which one end side is electrically connected to the column portion and the other end side is electrically connected to the outside. By performing each process mentioned above, the vacuum package which has an airtight chamber and a feedthrough part can be manufactured.

In particular, in the present invention, the exhaust holes used when evacuating and the through holes serving as the through holes of the feed-through portion are collectively formed on the first lid substrate side. Therefore, since it is not necessary to process the second lid substrate at all, it is possible to improve the bonding strength between the second lid substrate and the semiconductor substrate, and it is possible to improve the overall structure rather than forming holes in the two lid substrates. The bonding strength can be improved. Therefore, the degree of vacuum in the sealed chamber can be improved and high performance can be achieved.
In addition, since the exhaust holes and the through holes are formed in the first lid substrate in a collective manner, it can be easily manufactured without man-hours, and the manufacturing efficiency can be improved, compared with the case where each of the two lid substrates is formed. Can do.

In addition, since an insulating film is used when sealing the sealed chamber, unlike the case of using a metal film, a thick film can be formed without fear of film peeling. Therefore, the exhaust groove can be more reliably sealed. This also improves the degree of vacuum in the sealed chamber, leading to higher performance.
Further, since the storage chamber deeper than the exhaust groove is formed, the communication state between the through hole and the storage chamber is ensured even when the insulating film is formed. Therefore, the feedthrough portion can be formed immediately and easily without any special treatment after the sealing step. Also in this respect, efficient production can be performed.

  Further, the vacuum package manufacturing method according to the present invention is the above vacuum package manufacturing method according to the present invention, wherein the exhaust hole and the through hole gradually increase in diameter toward the semiconductor substrate during the lid substrate forming step. Is formed in a conical shape with a reduced diameter.

  In the vacuum package manufacturing method according to the present invention, the exhaust hole and the through hole are formed in a conical shape, and therefore, when the insulating film is formed, the insulating film is formed on the inner peripheral surface of the exhaust hole and the through hole. Can do. For this reason, since the insulating film tends to accumulate as it goes to the exhaust groove, the exhaust groove can be more reliably closed and sealed. Moreover, since each hole can be formed using sand blasting, it can be cheaply manufactured easily and efficiently.

  The method for manufacturing a vacuum package according to the present invention includes an insulating first lid substrate and a second lid substrate that are arranged in parallel with each other with a predetermined gap therebetween, and is sandwiched between these lid substrates. A frame portion formed in a frame shape, and a column portion provided in a sealed chamber surrounded by the frame portion and the first and second lid substrates and having both ends in contact with both lid substrates. And a semiconductor package having a semiconductor substrate, wherein the first lid substrate is formed with an exhaust hole and a through hole, and a storage chamber is formed so as to communicate with the through hole. A substrate forming step, a semiconductor substrate forming step of forming an exhaust groove in the semiconductor substrate so as to communicate with the exhaust hole when the first lid substrate is overlaid on the semiconductor substrate, and the semiconductor substrate only in a predetermined region Etched Etching steps for forming the sealed chamber communicating with the exhaust groove, the frame portion surrounding the periphery of the sealed chamber, and the column portion provided in the sealed chamber and in contact with the storage chamber at one end side, A bonding step of bonding the first lid substrate to one surface of the semiconductor substrate on which the exhaust groove is formed and bonding the second lid substrate to the other surface of the semiconductor substrate; and the exhaust groove And a vacuum step of bringing the sealed chamber into a vacuum state through the exhaust hole, and forming an insulating film on the surface of the first lid substrate with a film thickness that closes the exhaust groove in the vacuum, A sealing step of vacuum-sealing the sealed chamber, and plating a conductive material so as to fill the storage chamber and the through hole, and one end side is electrically connected to the support column and the other end side is externally Electrically connected feeds And forming a storage chamber deeper than the exhaust groove during the semiconductor substrate process, so that part of the insulating film falls into the storage chamber during the sealing process. And the insulating film is divided.

In the manufacturing method of the vacuum package according to the present invention, first, an exhaust hole for evacuating the sealed chamber to the first lid substrate, a through hole which is a through hole of the feedthrough portion, and the through hole communicate A lid substrate forming process for forming each storage chamber is performed. Moreover, when forming this storage chamber, it forms so that the depth may become deeper than the exhaust groove formed next.
Further, at the same time as or before or after this step, a semiconductor substrate step for forming an exhaust groove for evacuating the sealed chamber in the semiconductor substrate is performed. At this time, the exhaust groove is formed so as to communicate with the exhaust hole when the first lid substrate and the semiconductor substrate are overlapped.

  After the semiconductor substrate forming step, the semiconductor substrate is etched only in a predetermined region from the side where the exhaust groove is not formed, and an etching step is performed to form the frame portion and the column portion. At this time, the space surrounded by the frame portion becomes a sealed chamber when the first lid substrate and the second lid substrate are joined later. In addition, by this step, the exhaust groove formed earlier communicates with the space in the frame portion serving as a sealed chamber. Moreover, it will be in the state provided in this space where the support | pillar part which an end side touches the storage chamber formed previously becomes a sealed chamber.

Next, after both the lid substrate forming process and the etching process described above are completed, the first lid substrate is bonded to one surface of the semiconductor substrate in which the exhaust groove is formed, and the second lid substrate is bonded to the other surface of the semiconductor substrate. A joining step for joining to the surface is performed. Note that only the first lid substrate may be bonded first when performing the etching step. In any case, when the first lid substrate and the second lid substrate are bonded, the bonding process is completed.
By this step, the space surrounded by the frame portion becomes a sealed chamber, and both ends of the column portion provided in the sealed chamber are in contact with the first lid substrate and the second lid substrate. Thus, the one end side of the support column is in contact with the storage chamber. Moreover, the sealed chamber is in a state of communicating with the outside through the exhaust groove and the exhaust hole.

After the joining process, a vacuum process is performed for vacuuming the sealed chamber through the exhaust groove and the exhaust hole. That is, the semiconductor substrate bonded to both lid substrates is put into a vacuum chamber and evacuated. At this time, as described above, the sealed chamber is evacuated because it communicates with the outside through the exhaust groove and the exhaust hole.
And after performing this evacuation for a fixed time, the sealing process of vacuum-sealing a sealed chamber is performed. That is, an insulating film such as TEOS is formed on the surface of the first lid substrate in a vacuum. As a result, the surface of the first lid substrate naturally begins to fall and accumulate in the exhaust groove through the exhaust hole, and also begins to accumulate in the storage chamber through the through hole. In addition, when this process is performed, the insulating film is formed with a film thickness that closes the exhaust groove. As a result, the exhaust groove that communicates between the sealed chamber and the outside is closed, so that the sealed chamber can be vacuum-sealed.

  On the other hand, since the storage chamber is formed deeper than the exhaust groove, unlike the exhaust groove, it is not blocked by the insulating film. In other words, the insulating film is simply separated into the bottom of the storage chamber, and the insulating film is separated. Therefore, the storage chamber and the through hole can be kept in communication with each other.

  After this sealing process is completed, a plating process for forming a feedthrough portion in the through-hole that is a through hole is performed. That is, by performing electroplating or electroless plating, a feed-through portion is formed by growing a conductive material such as copper so as to fill the storage chamber and the through hole. The feed-through portion is a conduction path in which one end side is electrically connected to the column portion and the other end side is electrically connected to the outside. By performing each process mentioned above, the vacuum package which has an airtight chamber and a feedthrough part can be manufactured.

In particular, in the present invention, the exhaust holes used when evacuating and the through holes serving as the through holes of the feed-through portion are collectively formed on the first lid substrate side. Therefore, since it is not necessary to process the second lid substrate at all, it is possible to improve the bonding strength between the second lid substrate and the semiconductor substrate, and it is possible to improve the overall structure rather than forming holes in the two lid substrates. The bonding strength can be improved. Therefore, the degree of vacuum in the sealed chamber can be improved and high performance can be achieved.
In addition, since the exhaust holes and the through holes are formed in the first lid substrate in a collective manner, it can be easily manufactured without man-hours, and the manufacturing efficiency can be improved, compared with the case where each of the two lid substrates is formed. Can do.
Moreover, since the through hole and the storage chamber are integrally formed in the first lid substrate, the positional relationship between the two can be accurately created. Therefore, the reliability of the feedthrough portion can be improved.

In addition, since an insulating film is used when sealing the sealed chamber, unlike the case of using a metal film, a thick film can be formed without fear of film peeling. Therefore, the exhaust groove can be more reliably sealed. This also improves the degree of vacuum in the sealed chamber, leading to higher performance.
Further, since the storage chamber deeper than the exhaust groove is formed, the communication state between the through hole and the storage chamber is ensured even when the insulating film is formed. Therefore, the feedthrough portion can be formed immediately and easily without any special treatment after the sealing step. Also in this respect, efficient production can be performed.

  The vacuum package manufacturing method according to the present invention is the vacuum package manufacturing method according to the present invention, wherein the exhaust hole and the through hole are directed toward the semiconductor substrate in the lid substrate forming step. It is characterized in that it is formed in a conical shape with a gradually decreasing diameter.

  In the vacuum package manufacturing method according to the present invention, the exhaust hole and the through hole are formed in a conical shape, and therefore, when the insulating film is formed, the insulating film is formed on the inner peripheral surface of the exhaust hole and the through hole. Can do. For this reason, since the insulating film tends to accumulate as it goes to the exhaust groove, the exhaust groove can be more reliably closed and sealed. Moreover, since each hole can be formed using sand blasting, it can be cheaply manufactured easily and efficiently.

  The vacuum package manufacturing method according to the present invention is the vacuum package manufacturing method according to the present invention, wherein the storage chamber is gradually reduced in diameter toward the through hole during the lid substrate forming step. It is characterized by being formed in a conical shape with a diameter.

  In the vacuum package manufacturing method according to the present invention, the storage chamber is also formed in a conical shape by sandblasting, so that the processing speed can be increased and more efficient manufacturing can be performed.

  Further, the vacuum package manufacturing method according to the present invention is the vacuum package manufacturing method according to any one of the present invention described above, wherein the exhaust hole is also used as the exhaust hole in the lid substrate forming step. In the semiconductor substrate forming step, the exhaust groove is formed in the support column so as to communicate with the storage chamber.

  In the vacuum package manufacturing method according to the present invention, the exhaust holes and the through holes are not formed, but the through holes are also used as the exhaust holes, so that the number of holes formed in the first lid substrate can be reduced. it can. Therefore, the rigidity of the first lid substrate can be increased, and the bonding strength with the semiconductor substrate can be improved. Therefore, the degree of vacuum can be further improved to achieve high performance. Further, since the durability of the first lid substrate can be increased, the reliability can be improved. Furthermore, since the number of holes can be reduced, the size of the first lid substrate can be reduced and the size can be reduced.

  Further, in order to make the through hole also serve as an exhaust hole, the exhaust groove is formed in a region that will later become a support column so as to communicate with the storage chamber during the semiconductor substrate forming step. By doing so, the sealed chamber communicates with the outside through the exhaust groove and the through hole. Accordingly, during the vacuum process, the sealed chamber can be evacuated through the exhaust groove and the through hole. When the sealing process is performed, the insulating film that has fallen into the storage chamber through the through hole closes the exhaust groove and seals it. However, since the storage chamber itself is deeper than the exhaust groove, the entire storage chamber is not blocked, and the storage chamber and the through hole can be communicated with each other. Therefore, a feedthrough part can be reliably formed by performing a plating process.

  A vacuum package manufacturing method according to the present invention is the vacuum package manufacturing method according to any one of the above-described present invention, wherein the first lid substrate and the second lid substrate are formed in the bonding step. The semiconductor substrate is bonded by anodic bonding or room temperature bonding.

  In the method for manufacturing a vacuum package according to the present invention, the bonding is performed by performing anodic bonding or room temperature bonding when performing the bonding process. In particular, by performing commonly used anodic bonding, the semiconductor substrate and the first and second lid substrates can be reliably bonded without using a special technique. In addition, when room temperature bonding is performed, it is not necessary to raise the temperature unlike anodic bonding, and bonding can be performed at room temperature. Therefore, unlike anodic bonding, oxygen gas due to temperature rise is not generated, and there is no possibility of lowering the degree of vacuum in the sealed chamber.

  A vacuum package according to the present invention is manufactured by the method for manufacturing a vacuum package according to any one of the present invention.

  Since the vacuum package according to the present invention is manufactured by the above-described method, the degree of vacuum in the sealed chamber is improved and high performance is achieved. Moreover, since it is manufactured efficiently without man-hours, cost reduction can be achieved.

  An electronic device according to the present invention includes the vacuum package according to the present invention and an element provided in the sealed chamber.

  In the electronic device according to the present invention, since the element is provided in the sealed chamber with an improved degree of vacuum, it is possible to improve the performance and the reliability.

  The electronic device according to the present invention is the electronic device according to the present invention, wherein the element is supported by the frame portion via a beam portion, and has a predetermined interval with respect to the first and second lid substrates. A weight portion disposed at an interval, formed on the second lid substrate so as to be opposed to the weight portion in a state of being electrically connected to the column portion, and using the electrostatic attraction force for the weight portion. An excitation electrode that is excited and formed on the first lid substrate so as to face the weight portion while being electrically connected to the support column, and the weight portion in a vibrating state is displaced by receiving an angular velocity. In some cases, the apparatus includes a detection electrode that outputs a change in distance from the weight as a change in capacitance.

The electronic device according to the present invention can be used as an angular velocity sensor that detects angular velocity. That is, when a voltage is applied to the excitation electrode via the feedthrough portion, the excitation electrode excites the weight portion using electrostatic attraction. At this time, since the weight portion is supported by the beam portion with a predetermined gap (gap) with respect to the first and second lid substrates, the weight portion vibrates without contacting both lid substrates in the sealed chamber. . When the weight portion receives an angular velocity in this vibration state, the weight portion is twisted and displaced about the beam portion as a rotation center. Then, the detection electrode outputs the change in the distance from the weight part to the outside through the feedthrough part as the change in the capacitance. As a result, the angular velocity can be detected.
In particular, since the degree of vacuum in the sealed chamber is improved, the angular velocity can be detected with high sensitivity, and the reliability can be improved.

According to the manufacturing method of the vacuum package according to the present invention, it can be easily manufactured without man-hours, and the bonding strength between the semiconductor substrate and the lid substrate and the degree of vacuum in the sealed chamber are improved while ensuring the feedthrough portion. Thus, a high-performance vacuum package can be manufactured.
In addition, according to the vacuum package of the present invention, high performance can be achieved by improving the degree of vacuum of the sealed chamber, and cost can be reduced because it is efficiently manufactured without man-hours. .
In addition, according to the electronic device according to the present invention, since the above-described vacuum package is provided, it is possible to improve performance and improve reliability.

(First embodiment)
A first embodiment according to the present invention will be described below with reference to FIGS.
FIG. 1 is a cross-sectional view of the vacuum package 1 of the present embodiment. As shown in FIG. 1, a vacuum package 1 includes an insulating upper lid substrate (first lid substrate) 2 and a lower lid substrate (second lid substrate) 3 that are arranged in parallel with each other with a predetermined gap therebetween. And a semiconductor substrate 4 joined in a state of being sandwiched between the upper lid substrate 2 and the lower lid substrate 3.

  The semiconductor substrate 4 is, for example, a silicon substrate, and is provided in a sealed chamber 5 surrounded by a frame (frame portion) 4a formed in a frame shape and the frame 4a, the upper lid substrate 2 and the lower lid substrate 3. , Both lid substrates 2 and 3 are provided with islands (posts) 4b whose both ends are in contact with each other. The island 4b has a function of receiving an electrical signal from the outside via a feed-through portion 6 to be described later and outputting an electrical signal to the outside, and is provided in the sealed chamber 5 according to the purpose. The element which does not function is made to function. In the present embodiment, the elements are omitted. Depending on the type of element, metal wiring may be formed on the surface of the upper lid substrate 2 or the lower lid substrate 3 in the sealed chamber 5.

A storage chamber 10 is formed on one end side (upper lid substrate 2 side) of the island 4b. The storage chamber 10 is a chamber formed deeper than an exhaust groove 11 to be described later and wider than the diameter φ of the opening of the through hole 12, and serves as a gap of the feedthrough portion 6. . In addition, a part of the insulating film 13 is stored in the bottom of the storage chamber 10. This will be described in detail at a later stage of the manufacturing method.
The frame 4a on the upper lid substrate 2 side is formed with an exhaust groove 11 that allows the exhaust hole and the sealed chamber 5 to communicate with each other.

  The material of the upper lid substrate 2 and the lower lid substrate 3 is not limited as long as it is an insulating substrate, but representative examples include borosilicate glass and soda lime glass. Out of the lid substrates 2 and 3, the upper lid substrate 2 is formed with the exhaust holes 14 and the through holes 12 in an integrated manner. The exhaust hole 14 is formed at a position facing the exhaust groove 11 formed in the frame 4 a of the semiconductor substrate 4. As a result, the sealed chamber 5 communicates with the outside through the exhaust hole 14 and the exhaust groove 11. That is, the exhaust hole 14 and the exhaust groove 11 function as an exhaust passage when the sealed chamber 5 is evacuated. In the present embodiment, the exhaust hole 14 is formed in a conical shape (tapered cross section) in which the diameter gradually decreases as it goes toward the semiconductor substrate 4.

  The through-hole 12 serves as a through-hole of a feed-through portion 6 described later, and is formed so as to face the storage chamber 10 formed in the island 4b of the semiconductor substrate 4. Thereby, the through-hole 12 and the storage chamber 10 are connected. Similar to the exhaust hole 14, the through hole 12 is also formed in a conical shape (tapered cross section) in which the diameter gradually decreases toward the semiconductor substrate 4.

An insulating film 13 such as TEOS is formed on the upper lid substrate 2. At this time, since both the exhaust hole 14 and the through hole 12 are formed in a conical shape, the insulating film 13 is also formed on the inner peripheral surfaces of the exhaust hole 14 and the through hole 12. Further, the exhaust groove 11 is closed on the exhaust hole 14 side by the insulating film 13. Thereby, the sealed chamber 5 is sealed in a vacuum atmosphere.
The through-hole 12 and the storage chamber 10 are formed with a feed-through portion 6 in which a conductive material such as copper is buried by plating. One end side of the feedthrough portion 6 is electrically connected to the island 4b, and the other end side is exposed to the outside so that it can be electrically connected. That is, the feedthrough 6 is used as a conduction path that connects the island 4b and the outside.

  Next, a method for manufacturing the vacuum package 1 configured as described above will be described below with reference to FIGS. 2 to 11 are cross-sectional views showing the respective steps when manufacturing the vacuum package 1. In addition, the manufacturing process shown below is performed by the semiconductor substrate 4 and the lid substrates 2 and 3 having a size capable of manufacturing a large number of vacuum packages 1, and is finally separated into the minute vacuum package 1. However, in FIGS. 2 to 11, the vacuum package 1 is illustrated as being manufactured for the sake of simplicity.

The manufacturing method of the vacuum package 1 of the present embodiment is manufactured by appropriately performing a semiconductor substrate forming process, a lid substrate forming process, an etching process, a bonding process, a vacuum process, a sealing process, and a plating process. Is the method.
In addition, among these each process, each process except a vacuum process, a sealing process, and a plating process may be performed simultaneously, and process order is not limited. In the present embodiment, a case where the upper lid substrate 2 is bonded to the semiconductor substrate 4 first, an etching process is performed, and then the lower lid substrate 3 is bonded will be described as an example.

First, a semiconductor substrate forming process for forming the exhaust groove 11 and the storage chamber 10 in the semiconductor substrate 4 is performed. That is, after the semiconductor substrate 4 shown in FIG. 2 is prepared, the exhaust groove 11 is first formed on the semiconductor substrate 4 by a semiconductor processing technique such as photolithography or etching, as shown in FIG. At this time, as etching, wet etching with TMAH (Tetramethyl ammonium hydroxid) or dry etching with RIE (Reactive Ion Etching) is simple. When wet etching is performed with TMAH, a SiO ₂ film and when dry etching is performed with RIE, a photoresist may be used as a mask.

  The depth of the exhaust groove 11 is preferably equal to or less than the thickness of the insulating film 13 to be formed later. Here, the thickness of the insulating film 13 to be formed later is, for example, about several μm to 20 μm because of stress. However, as the depth of the exhaust hole 14 is increased, the film formation state is slightly inferior, and the film thickness is expected to be half or less. Therefore, it is more preferable that the depth of the exhaust groove 11 is within a range of about 0.5 μm to 2 μm.

Next, as shown in FIG. 4, the storage chamber 10 is formed on the semiconductor substrate 4 by the semiconductor processing technique such as the photolithography technique and etching described above. At this time, the storage chamber 10 is formed deeper than the exhaust groove 11 and wider than the diameter φ of the opening of the through hole 12. For example, it is preferable that the depth is 2 μm or more and the width is about 5 μm.
Thereby, a semiconductor substrate formation process is complete | finished. In addition, although the case where the exhaust groove 11 was formed previously was shown, it is not restricted to this case, You may form the storage chamber 10 previously, and may form the exhaust groove 11 after that.

  Also, a lid substrate forming step for forming the exhaust holes 14 and the through holes 12 in the upper lid substrate 2 is performed simultaneously with or before or after the above steps. First, after the upper lid substrate 2 shown in FIG. 5 is prepared, the exhaust hole 14 and the through hole 12 are formed by sandblasting, ultrasonic processing, and laser irradiation, as shown in FIG. At this time, the exhaust hole 14 and the through hole 12 are formed to have a conical shape having a tapered cross section. In particular, the formation of the holes by sandblasting is a preferable method because the exhaust holes 14 and the through holes 12 can be formed in a forward tapered shape in addition to being inexpensive, simple and efficient.

Next, a bonding process for bonding the upper lid substrate 2 to the semiconductor substrate 4 first is performed. That is, as shown in FIG. 7, after the upper lid substrate 2 in which the exhaust holes 14 and the through holes 12 are formed is superimposed on one surface of the semiconductor substrate 4 in which the exhaust grooves 11 and the storage chambers 10 are formed, The upper lid substrate 2 and the semiconductor substrate 4 are bonded by, for example, anodic bonding. However, in this case, the upper lid substrate 2 is made of borosilicate glass or soda lime glass. As conditions for performing anodic bonding, for example, the temperature is about 400 ° C. and the voltage is about 100V. Thereby, the upper lid substrate 2 and the semiconductor substrate 4 can be easily and firmly bonded.
In addition, when metal wiring is provided in the sealed chamber 5, it is necessary to adjust the temperature at the time of anodic bonding so as not to affect these metal wiring.

Next, the semiconductor substrate 4 is etched only in a predetermined region, the sealed chamber 5 communicating with the exhaust groove 11, the frame 4 a surrounding the sealed chamber 5, and the storage chamber 10 provided in the sealed chamber 5 on one end side. The etching process for forming the islands 4b included in each is performed.
That is, as shown in FIG. 8, the frame 4a and the island 4b are formed from the other surface side of the semiconductor substrate 4 by etching only a predetermined region by the semiconductor processing technique such as the above-described photolithography technique or etching. . At this time, the space surrounded by the frame 4a becomes the sealed chamber 5 when the lower lid substrate 3 is joined later. In addition, by this step, the exhaust groove 11 formed earlier communicates with the space in the frame 4 a serving as the sealed chamber 5. Further, the island 4b having the storage chamber 10 formed on the one end side is provided in the space to be the sealed chamber 5.

Next, a bonding process for bonding the lower lid substrate 3 to the other surface of the semiconductor substrate 4 is performed. That is, after the lower lid substrate 3 shown in FIG. 9 is prepared, the lower lid substrate 3 is overlaid on the other surface of the semiconductor substrate 4 as shown in FIG. And the lower lid board | substrate 3 is joined by the method similar to the time of joining of the upper lid board | substrate 2 mentioned above. Note that when the lower lid substrate 3 is bonded, the bonding process is completed.
By joining the lower lid substrate 3, the space surrounded by the frame 4 a becomes the sealed chamber 5, and both ends of the island 4 b provided in the sealed chamber 5 are in contact with the upper lid substrate 2 and the lower lid substrate 3. It becomes. In addition, the sealed chamber 5 is in communication with the outside through the exhaust groove 11 and the exhaust hole 14.

  Next, a vacuum process is performed in which the sealed chamber 5 is evacuated through the exhaust groove 11 and the exhaust hole 14. That is, the semiconductor substrate 4 bonded to both the lid substrates 2 and 3 is put into a vacuum chamber such as a chamber (not shown) and then evacuated. At this time, as described above, since the sealed chamber 5 communicates with the outside through the exhaust groove 11 and the exhaust hole 14, it is surely evacuated.

  Then, after performing this evacuation for a certain time, an insulating film 13 is formed on the surface of the upper lid substrate 2 with a film thickness that closes the exhaust groove 11, and a sealing process for vacuum-sealing the sealed chamber 5 is performed. That is, an insulating film 13 such as TEOS is formed on the surface of the upper lid substrate 2 in a vacuum so that the film thickness is larger than that of the exhaust groove 11. At this time, since the film thickness becomes thinner as it goes deeper into the exhaust hole 14, a film thickness larger than the exhaust groove 11 is required at least. Further, there is a possibility that chipping of about several μm may occur in the exhaust hole 14, and even if chipping occurs, it is preferable that the film thickness be sufficient to cover this. Considering these, it is preferable to form the insulating film 13 with a film thickness of about 20 μm.

  Thus, as shown in FIG. 11, the insulating film 13 is formed on the inner peripheral surfaces of the exhaust hole 14 and the through hole 12 as well as the surface of the upper lid substrate 2. Further, the insulating film 13 starts to fall and accumulate in the exhaust groove 11 through the exhaust hole 14, and also begins to accumulate in the storage chamber 10 through the through hole 12. Then, the exhaust groove 11 that finally communicates the sealed chamber 5 with the outside is closed, and the sealed chamber 5 can be vacuum-sealed.

  On the other hand, since the storage chamber 10 is deeper than the exhaust groove 11 and wider than the diameter φ of the through hole 12, it is not blocked by the insulating film 13 unlike the exhaust groove 11. That is, the insulating film 13 is simply separated into the bottom of the storage chamber 10 and the insulating film 13 is separated. Accordingly, the storage chamber 10 and the through hole 12 can be kept in communication with each other.

  Next, after the sealing process is completed, a plating process for forming the feedthrough portion 6 in the through hole 12 which is a through hole is performed. That is, electroplating or electroless plating is performed to grow a conductive material so as to fill the storage chamber 10 and the through hole 12 to form a field through portion.

  Specifically, the electroless plating is once performed, and then the through hole 12 and the storage chamber 10 are filled by electroplating, and unnecessary portions are removed to form the feedthrough portion 6. Electroless plating includes copper (copper sulfate aqueous solution + reducing agent), nickel (nickel sulfate aqueous solution or nickel chloride aqueous solution + reducing agent), gold (gold cyanide complex aqueous solution + reducing agent) and silver (silver cyanide). (Aqueous solution + reducing agent) or the like is used.

  Alternatively, the feedthrough portion 6 is formed by applying a voltage to the end of the island 4b in contact with the storage chamber 10 from a voltage application wiring to the island 4b (not shown) and directly growing electroplating from the storage chamber 10 side. For example, the feedthrough portion 6 is formed by applying a negative voltage in a solution such as nickel sulfate or nickel chloride to grow a nickel plating product. Alternatively, the feedthrough portion 6 is formed by applying a negative voltage in a solution such as copper pyrophosphate or copper sulfate to grow a copper plating product. The plated product to be grown may be gold, rhodium, palladium, platinum or the like. In the case of gold, the plating solution used is a potassium dicyanogold (I) acid aqueous solution. In the case of rhodium, a solution of rhodium and sulfuric acid or rhodium and phosphoric acid is used. When the diamminepalladium (II) (PD (NH3) 2 (NO2) 2 aqueous solution is platinum, a solution of platinum and diaminonitrite is used.

The vacuum package 1 shown in FIG. 1 can be manufactured by performing the said plating process. In particular, in the manufacturing method of the present embodiment, the exhaust holes 14 used when evacuating and the through holes 12 that become the through holes of the feedthrough portion 6 are collectively formed on the upper lid substrate 2 side. . Therefore, since it is not necessary to process the lower lid substrate 3 at all, the bonding strength between the lower lid substrate 3 and the semiconductor substrate 4 can be improved, and the entire lid substrate 2 and 3 can be formed as compared with the case where holes are formed in the two lid substrates 2 and 3 respectively. Joint strength can be improved. Therefore, the degree of vacuum in the sealed chamber 5 can be improved, and high performance can be achieved.
Further, since the exhaust holes 14 and the through holes 12 are formed in the upper lid substrate 2 in an integrated manner, it can be easily manufactured with less man-hours than the formation of the two lid substrates 2 and 3 respectively. Efficiency can be increased.

In addition, since the insulating film 13 is used when sealing the sealed chamber 5, unlike the case where a metal film is used, a thick film can be formed without fear of film peeling. Therefore, the exhaust groove 11 can be more reliably sealed. Also from this, the degree of vacuum of the sealed chamber 5 can be improved, leading to higher performance.
Further, since the storage chamber 10 deeper than the exhaust groove 11 is formed, the communication state between the through hole 12 and the storage chamber 10 is ensured even if the insulating film 13 is formed. Therefore, the feedthrough portion 6 can be formed immediately and easily without special processing after the sealing step. Also in this respect, efficient production can be performed.

  Further, since the exhaust hole 14 is formed in a conical shape, the insulating film 13 can be formed on the inner peripheral surface of the exhaust hole 14 when the insulating film 13 is formed. Therefore, since the insulating film 13 tends to accumulate as it goes to the exhaust groove 11, the exhaust groove 11 can be more reliably closed and sealed. In addition, since the holes can be formed by using sandblasting, it is possible to manufacture easily and efficiently at a lower cost.

  Moreover, according to the vacuum package 1 manufactured in this way, high performance can be achieved by improving the degree of vacuum of the sealed chamber 5, and the cost is reduced because it is efficiently manufactured without man-hours. Can be planned.

  In the first embodiment, an example in which the first lid substrate is the upper lid substrate 2 and the exhaust holes 14 and the through holes 12 are formed in the upper lid substrate 2 is shown. The substrate may be the lower lid substrate 3, and the exhaust holes 14 and the through holes 12 may be collectively formed in the lower lid substrate 3. In this case, the exhaust groove 11 and the storage chamber 10 may be formed on the other surface side of the semiconductor substrate 4.

In the first embodiment, anodic bonding is performed when performing the bonding process. However, bonding may be performed by room temperature bonding. In this case, the surface is activated using ions such as argon and then bonded by pressure bonding. Therefore, unlike anodic bonding, oxygen gas may be generated due to a chemical reaction during bonding. There is no fear of lowering the vacuum in the sealed chamber 5. Therefore, the vacuum package 1 can be improved in performance.
In the case of performing this room temperature bonding, the first and second lid substrates are not limited to borosilicate glass or soda lime glass, and may be anything.
When anodic bonding is performed, a voltage application wiring (not shown) is patterned on the surface of the first and second lid substrates or the surface of the semiconductor substrate 4, and voltage is applied to the wiring to perform anodic bonding. If it carries out, the 1st and 2nd lid substrate and the semiconductor substrate 4 can be uniformly joined over each whole substrate.

(Second Embodiment)
Next, a second embodiment according to the present invention will be described with reference to FIG. In the second embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.
The difference between the second embodiment and the first embodiment is that the storage chamber 10 is formed on the island 4b of the semiconductor substrate 4 in the first embodiment. However, in the second embodiment, the storage chamber 10 is formed on the upper lid substrate 2. This is the point that is formed.

  FIG. 12 is a cross-sectional view of the vacuum package 20 of the present embodiment. As shown in FIG. 12, the vacuum package 20 is formed on the upper lid substrate 2 side so that the storage chamber 10 communicates with the through hole 12. Similar to the first embodiment, the storage chamber 10 is formed deeper than the exhaust groove 11 and wider than the diameter φ of the opening of the through hole 12.

Next, a method for manufacturing the vacuum package 20 of the present embodiment will be briefly described. Since the basic manufacturing method is the same as that of the first embodiment, different steps will be mainly described.
First, in the semiconductor substrate forming step, only the exhaust groove 11 is formed in the semiconductor substrate 4. At this time, the formation method of the exhaust groove 11 and the depth of the exhaust groove 11 are the same. Next, in the lid substrate forming step, the storage chamber 10 is formed so as to communicate with the upper lid substrate 2 not only through the exhaust holes 14 and the through holes 12 but also through the through holes 12. At this time, the storage chamber 10 may be formed by wet etching or dry etching. Next, a bonding process is performed in which the upper lid substrate 2 in which the exhaust holes 14, the through holes 12 and the storage chamber 10 are formed is bonded to one surface of the semiconductor substrate 4 in which the exhaust grooves 11 are formed.

Next, an etching process is performed in which the semiconductor substrate 4 is etched by a predetermined region from the other surface side to form the frame 4a and the island 4b. Thereby, as shown in FIG. 12, one end side of the island 4b is in contact with the storage chamber 10 formed in the upper lid substrate 2.
Thereafter, similarly to the first embodiment, the vacuum package 20 shown in FIG. 12 can be manufactured by sequentially performing a bonding process, a vacuum process, a sealing process, and a plating process.

  Also in the manufacturing method of the vacuum package 20 of this embodiment, there can exist the same effect as 1st Embodiment. In particular, in the case of this embodiment, since the through hole 12 and the storage chamber 10 are integrally formed in the upper lid substrate 2 in advance, the positional relationship between the two can be accurately created. That is, in the first embodiment, since the through hole 12 is formed on the upper lid substrate 2 side and the storage chamber 10 is formed on the semiconductor substrate 4 side, the alignment accuracy (about 10 μm to 20 μm) at the time of bonding is considered. Thus, it is necessary to form the through hole 12 and the storage chamber 10 with a slight margin. On the other hand, in this embodiment, since it can form with the alignment precision of lithography (about 0.5 micrometer-1 micrometer), while being able to improve the reliability of the feedthrough part 6, size reduction can be achieved.

In the second embodiment, in the lid substrate forming step, the storage chamber 10 is formed in a conical shape (tapered cross section) with the diameter gradually decreasing toward the through hole 12 as shown in FIG. It doesn't matter. That is, the through hole 12 and the storage chamber 10 are formed in a drum shape.
In this case, since the storage chamber 10 can also be formed by sandblasting, the processing speed can be increased and more efficient production can be performed.

(Third embodiment)
Next, a third embodiment according to the present invention will be described with reference to FIG. In the third embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.
The difference between the third embodiment and the first embodiment is that, in the first embodiment, the exhaust hole 14 and the through hole 12 are separately formed in the upper lid substrate 2, but in the third embodiment, the through hole 12 is formed. And the exhaust hole 14 is also used.

  FIG. 14 is a cross-sectional view of the vacuum package 30 of the present embodiment. As shown in FIG. 14, the vacuum package 30 includes the upper lid substrate 2 in which only the through hole 12 is formed, and the exhaust groove 11 is communicated with the through hole 12. The exhaust groove 11 is formed in the island 4b, not the frame 4a, although it is the same semiconductor substrate 4.

Next, a method for manufacturing the vacuum package 30 of this embodiment will be briefly described. Since the basic manufacturing method is the same as that of the first embodiment, different steps will be mainly described.
First, in the semiconductor substrate forming step, the storage chamber 10 is formed, and the exhaust groove 11 is formed in a region to be the island 4 b so as to communicate with the storage chamber 10. Next, only the through hole 12 is formed in the upper lid substrate 2 during the lid substrate forming step. Next, the upper lid substrate 2 in which the through hole 12 is formed is bonded to one surface of the semiconductor substrate 4 in which the exhaust groove 11 and the storage chamber 10 are formed. Next, an etching process for forming the frame 4 a and the island 4 b on the semiconductor substrate 4 is performed, and a bonding process for bonding the lower lid substrate 3 to the other surface of the semiconductor substrate 4 is performed.

  At this time, the sealed chamber 5 is in communication with the outside through the exhaust groove 11 and the through hole 12. Therefore, the inside of the sealed chamber 5 can be evacuated reliably through the exhaust groove 11 and the through hole 12 during the vacuum process. When the sealing process is performed, the insulating film 13 that has fallen into the storage chamber 10 through the through hole 12 closes the exhaust groove 11 and seals it. However, since the storage chamber 10 itself is deeper than the exhaust groove 11, the entire storage chamber 10 is not blocked, and the storage chamber 10 and the through hole 12 can be communicated with each other. Therefore, the feedthrough part 6 can be reliably formed by performing a plating process.

  In particular, in the manufacturing method of the present embodiment, since the exhaust holes 14 are also used as the through holes 12, the number of holes formed in the upper lid substrate 2 can be reduced. Therefore, the rigidity of the upper lid substrate 2 can be increased, and the bonding strength with the semiconductor substrate 4 can be improved. For this reason, the risk of vacuum leakage is reduced, so that the degree of vacuum can be further improved and higher performance can be achieved. Moreover, since the durability of the upper lid substrate 2 can be improved, the reliability can be improved. Furthermore, since the number of holes can be reduced, the size of the upper lid substrate 2 can be reduced and the size can be reduced.

In addition, although the said 3rd Embodiment showed the example which made the exhaust hole 14 serve as the through-hole 12 with respect to the vacuum package 1 of 1st Embodiment, the vacuum package 20 of the said 2nd Embodiment. In this case, the exhaust hole 14 may also be used as the through hole 12.
FIG. 15 is a cross-sectional view showing a modification of the vacuum package 20 of the second embodiment. As shown in FIG. 15, in the vacuum package 40, the exhaust groove 11 is formed in the island 4 b so as to communicate with the storage chamber 10 formed in the upper lid substrate 2. According to the vacuum package 40, in addition to the operational effects of the second embodiment, the operational effects of the third embodiment can also be achieved.

(Fourth embodiment)
Next, a fourth embodiment according to the present invention will be described with reference to FIGS. 16 is an exploded perspective view showing the electronic device 50 of the present embodiment, FIG. 17 is a plan view of the semiconductor substrate 63 seen from above through the upper lid substrate 61, and FIG. 18 is shown in FIG. It is sectional drawing along the AA line. In the present embodiment, as the electronic device 50, an angular velocity sensor that detects an angular velocity will be described as an example.

  As shown in FIGS. 16 to 18, the electronic device 50 of this embodiment includes a vacuum package 60 and a weight portion (element) 51 provided in a sealed chamber 67 of the vacuum package 60. The vacuum package 60 includes an insulating upper lid substrate (first lid substrate) 61 and a lower lid substrate (second lid substrate) 62 arranged in parallel with each other at a predetermined interval, an upper lid substrate 61, And a semiconductor substrate 63 joined in a state of being sandwiched between the lower lid substrate 62 and the lower lid substrate 62.

In this embodiment, as the semiconductor substrate 63, the silicon support layer 64, the silicon dioxide (SiO ₂ ) BOX layer 65 formed on the silicon support layer 64, and the silicon formed on the BOX layer 65 are used. An example using an SOI (Silicon On Insulator) substrate 63 having an active layer 66 will be described.

  The SOI substrate 63 is provided in a sealed chamber 67 surrounded by a frame (frame portion) 63a formed in a frame shape and the frame 63a, the upper lid substrate 61, and the lower lid substrate 62. 62 is provided with five islands (posts) 63b whose both ends are in contact with each other. Of the five islands 63b, the four islands 63b are used as conduction paths for applying a voltage to the excitation electrode 53 described later from the outside via the feedthrough portion 68. The remaining one island 63b is used as a conduction path for outputting a detection result to the outside from a detection electrode 54 described later via the feedthrough portion 68.

  A storage chamber 69 is formed on one end side (upper lid substrate 61 side) of these five islands 63b. The storage chamber 69 is a chamber formed deeper than the exhaust groove 70 and wider than the diameter φ of the opening of the through hole 71 and serves as a gap of the feedthrough portion 68. Further, among the five islands 63b, one island 63b is formed with an exhaust groove 70 connected to the storage chamber 69 while the sealed chamber 67 and the through hole 71 communicate with each other.

  The material of the upper lid substrate 61 and the lower lid substrate 62 is not limited as long as it is an insulating substrate, but representative examples include borosilicate glass and soda lime glass. Among the lid substrates 61 and 62, the upper lid substrate 61 is formed with a through hole 71 serving as a through hole of the feedthrough portion 68 at a position facing the five islands 63b. Thereby, the through hole 71 and the storage chamber 69 communicate with each other. Further, the through hole 71 is formed in a conical shape (tapered cross section) in which the diameter gradually decreases toward the SOI substrate 63.

  Of the five through holes 71, the through hole 71 communicating with the storage chamber 69 connected to the exhaust groove 70 is a hole that also serves as an exhaust hole, and when the sealed chamber 67 is evacuated together with the exhaust groove 70. It functions as an exhaust passage.

  An insulating film 72 such as TEOS is formed on the upper lid substrate 61. At this time, since the through holes 71 are both formed in a conical shape, an insulating film 72 is also formed on the inner peripheral surface of the through hole 71. Further, the exhaust groove 70 is closed by the insulating film 72 on the through hole 71 side. Thereby, the sealed chamber 67 is sealed in a vacuum atmosphere. The through-hole 71 and the storage chamber 69 are formed with a feed-through portion 68 in which a conductive material such as copper is buried by plating. One end side of the feedthrough portion 69 is electrically connected to the island 63b, and the other end side is exposed to the outside so that it can be electrically connected.

The weight portion 51 is supported by the frame 63a via four beams (beam portions) 52, and has a predetermined interval, that is, an excitation gap G with respect to the upper lid substrate 61 and the lower lid substrate 62. It is arrange | positioned in the sealed chamber 67 so that it may be suspended by. The four beams 52 are supported on the base end side by a frame 63a formed in a quadrangular shape, and are formed so as to extend inward from the intermediate positions of the four sides of the frame 63a.
In particular, in the present embodiment, since there are four beams 52, the angular velocities in the X-axis and Y-axis directions can be detected most efficiently. However, the number of beams 52 is not limited to four, and may be one or more. Even in this case, it is possible to detect the biaxial angular velocity by devising the shape of the weight portion 51.

In addition, on the inner surface of the lower lid substrate 62 in the sealed chamber 67, an excitation electrode 53 is formed at a position facing the weight portion 51 to excite the weight portion 51 using electrostatic attraction. The excitation electrode 53 is formed in a size having substantially the same area as the weight portion 51, and is electrically connected to one of the islands 63b.
In addition, on the inner surface of the upper lid substrate 61 in the sealed chamber 67, when the vibrating weight 51 is displaced by receiving an angular velocity at a position facing the weight 51, a change in distance from the weight 51 is statically suppressed. A detection electrode 54 that outputs the change in capacitance is formed. Four detection electrodes 54 are formed so as not to overlap the beam 52, and each is connected to the remaining four islands 63b in an electrode manner.

  A case where the angular velocity is detected by the electronic device 50 configured as described above will be described. First, a voltage is applied to the excitation electrode 53 via the feedthrough portion 68, and the weight portion 51 is vibrated using electrostatic attraction. At this time, the weight portion 51 is supported by the beam 52 with the excitation gap G open with respect to the upper lid substrate 61 and the lower lid substrate 62, so that it contacts the lid substrates 61 and 62 in the sealed chamber 67. Vibrate without doing. When the weight portion 51 receives an angular velocity in this vibration state, the weight portion 51 is twisted and displaced with the beam 52 as the rotation center. Then, the detection electrode 54 outputs the change in the distance from the weight part 51 to the outside through the feedthrough part 68 as a change in capacitance. As a result, angular velocities around the two axes of the X axis and the Y axis can be detected.

  Next, a method for manufacturing the electronic device 50 configured as described above will be described below with reference to FIGS. FIG. 19 to FIG. 33 are cross-sectional views showing the respective steps in manufacturing the vacuum package 60. FIGS. 19 to 33 are cross-sectional views taken along line AA shown in FIG. Further, the manufacturing process shown below is performed by the SOI substrate 63 and the lid substrates 61 and 62 having a size capable of manufacturing a large number of electronic devices 50, and finally is separated into minute electronic devices 50. However, in order to simplify the description, the single electronic device 50 is illustrated as being manufactured.

The manufacturing method of the electronic device 50 of the present embodiment is manufactured by appropriately performing a semiconductor substrate forming process, a lid substrate forming process, an etching process, a bonding process, a vacuum process, a sealing process, and a plating process. Is the method.
In addition, among these each process, each process except a vacuum process, a sealing process, and a plating process may be performed simultaneously, and process order is not limited. In the present embodiment, an example will be described in which the upper lid substrate 61 is first bonded to the SOI substrate 63, an etching process is performed, and then the lower lid substrate 62 is bonded.

  First, a semiconductor substrate forming process for forming the exhaust groove 70 and the storage chamber 69 in the SOI substrate 63 is performed. At the same time, in this step, the upper portions of the weight 51, the beam 52, the frame 63a, and the island 63b are formed. First, an SOI substrate 63 shown in FIG. 19 is prepared. By using the SOI substrate 63, the BOX layer 65 can be used as an etching stop, so that the thickness of the beam 52 can be determined by the thickness of the silicon active layer 66, and desired vibration characteristics can be easily obtained. .

Next, as shown in FIG. 20, an exhaust groove 70 is formed on the silicon active layer 66 of the SOI substrate 63 by a semiconductor processing technique such as photolithography or etching. At this time, as etching, wet etching with TMAH (Tetramethyl ammonium hydroxid) or dry etching with RIE (Reactive Ion Etching) is simple. When wet etching is performed with TMAH, a SiO ₂ film and when dry etching is performed with RIE, a photoresist may be used as a mask.

  The depth of the exhaust groove 70 is preferably equal to or less than the thickness of the insulating film 72 to be formed later. Here, the thickness of the insulating film 72 to be formed later is, for example, about several μm to 20 μm because of stress. However, as the depth of the through hole 71 is increased, the film formation state is slightly inferior, and the film thickness is expected to be half or less. Therefore, it is more preferable that the depth of the exhaust groove 70 is formed within a range of about 0.5 μm to 2 μm.

  Next, as shown in FIG. 21, a storage chamber 69 and an excitation gap G between the weight portion 51 and the upper lid substrate 61 are formed on the silicon active layer 66 by a semiconductor processing technique such as wet etching or dry etching. To do. At this time, the storage chamber 69 is formed deeper than the exhaust groove 70 and wider than the diameter of the opening of the through hole 71. For example, it is preferable that the depth is 2 μm or more and the width is about 5 μm.

Next, as shown in FIG. 22, an excitation gap G between the weight portion 51 and the lower lid substrate 62 is formed on the silicon support layer 64 by a semiconductor processing technique such as wet etching or dry etching. Note that the above-described process order may be changed.
Next, as shown in FIG. 23, regions other than the frame 63a, the beam 52, the weight portion 51, and the island 63b in the silicon active layer 66 are removed by a semiconductor processing technique such as wet etching or dry etching. Subsequently, as shown in FIG. 24, the exposed BOX layer 65 is removed by a semiconductor processing technique such as wet etching or dry etching.

  Thereby, the exhaust groove 70 and the storage chamber 69 are formed, and the upper portion of the weight portion 51, the beam 52, the frame 63a, and the island 63b can be formed. At this point, the semiconductor substrate forming process is completed.

  Further, a lid substrate forming step for forming the through hole 71 in the upper lid substrate 61 is performed simultaneously with or before or after the above step. In this step, the detection electrode 54 is formed at the same time. First, after preparing the upper lid substrate 61 shown in FIG. 25, through holes 71 are formed as shown in FIG. 26 by sand blasting, ultrasonic processing, or laser irradiation. At this time, the through hole 71 is formed in a conical shape having a tapered cross section. In particular, the formation of the holes by sandblasting is a preferable method because the through holes 71 can be formed in a forward tapered shape in addition to being inexpensive, simple and efficient.

  Next, as shown in FIG. 27, the detection electrode 54 is formed on the inner surface of the upper lid substrate 61 with a conductive film. The conductive film is made of a material containing at least one of Al, Cr, Pt, Cu, and W, and includes at least one layer. In addition, when there are a plurality of layers, the material of each layer may be different. These conductive films are once formed on the entire surface of the upper lid substrate 61 by sputtering, MOCVD, or the like, and then patterned by wet etching, dry etching, or lift-off. Thereby, the detection electrode 54 can be formed. When the detection electrode 54 is formed, the lid substrate forming process is completed.

Next, a bonding process for bonding the upper lid substrate 61 to the SOI substrate 63 first is performed. That is, as shown in FIG. 28, the upper lid substrate 61 in which the through hole 71 is formed is overlaid on one surface of the SOI substrate 63 in which the exhaust groove 70 and the storage chamber 69 are formed, and then the upper lid substrate 61 is placed. Are bonded to the SOI substrate 63 by, for example, anodic bonding. However, in this case, the upper lid substrate 61 is made of borosilicate glass or soda lime glass. As conditions for performing anodic bonding, for example, the temperature is about 400 ° C. and the voltage is about 100V. Thereby, the upper lid substrate 61 and the SOI substrate 63 can be easily and firmly bonded.
Note that the bonding is performed while paying attention to the temperature so as not to affect the detection electrode 54 during the anodic bonding. For example, when the detection electrode 54 is formed of an Al conductive film, bonding is performed at a temperature of 400 ° C. or lower.

Next, an etching process is performed in which the silicon support layer 64 of the SOI substrate 63 is etched only in a predetermined region to form the frame 63a, the island 63b, the weight portion 51, and the beam 52 that are formed only on the upper portion.
That is, as shown in FIG. 29, regions other than the frame 63a, the weight portion 51, the beam 52, and the island 63b are removed from the other surface side of the SOI substrate 63 by a semiconductor processing technique such as wet etching or dry etching. Thereby, the frame 63a, the island 63b, the weight portion 51, and the beam 52 can be formed. Further, the space surrounded by the frame 63a becomes a sealed chamber 67 when the lower lid substrate 62 is joined later. Further, the exhaust groove 70 formed earlier communicates with the space in the frame 63 a serving as the sealed chamber 67. Further, the island 63 b having the storage chamber 69 formed on one end side is provided in the space to be the sealed chamber 67.
In addition, when deep etching (Deep RIE) using a Bosch process is applied when etching is performed, the silicon support layer 64 can be processed at an angle close to vertical, and therefore, highly accurate processing can be performed.

  Next, a bonding process for bonding the lower lid substrate 62 to the other surface of the SOI substrate 63 is performed. However, before that, the excitation electrode 53 is formed on the lower lid substrate 62. That is, after the lower lid substrate 62 shown in FIG. 30 is prepared, the excitation electrode 53 is formed on the inner surface of the lower lid substrate 62 as shown in FIG. At this time, the excitation electrode 53 is formed by the same method as the detection electrode 54 described above.

After the excitation electrode 53 is formed, the lower lid substrate 62 is overlaid on the other surface of the SOI substrate 63 as shown in FIG. Then, the lower lid substrate 62 is bonded by the same method as that for bonding the upper lid substrate 61 described above. Note that when the lower lid substrate 62 is bonded, the bonding process is completed.
By joining the lower lid substrate 62, the space surrounded by the frame 63a becomes a sealed chamber 67, and both ends of the island 63b provided in the sealed chamber 67 are in contact with the upper lid substrate 61 and the lower lid substrate 62. It becomes. Further, the sealed chamber 67 communicates with the outside through the exhaust groove 70 and the through hole 71.

  Next, a vacuum process is performed in which the sealed chamber 67 is evacuated through the exhaust groove 70 and the through hole 71. That is, the SOI substrate 63 bonded to both the lid substrates 61 and 62 is put into a vacuum chamber such as a chamber (not shown) and then evacuated. At this time, as described above, since the sealed chamber 67 communicates with the outside via the exhaust groove 70 and the through hole 71, it is surely evacuated.

  Then, after performing this evacuation for a certain time, an insulating film 72 is formed on the surface of the upper lid substrate 62 with a film thickness that closes the exhaust groove 70, and a sealing process for vacuum-sealing the sealed chamber 67 is performed. That is, an insulating film 72 such as TEOS is formed on the surface of the upper lid substrate 61 so as to be thicker than the exhaust groove 70 in a vacuum. At this time, since the film thickness decreases as it goes deeper into the through hole 71, the film thickness is required to be at least as large as the exhaust groove 70, and it is preferable to form the insulating film 72 with a film thickness of about 20 μm.

  Thus, as shown in FIG. 33, the insulating film 72 is formed on the inner peripheral surface of the through hole 71 as well as the surface of the upper lid substrate 61. In addition, the insulating film 72 falls into the storage chamber 69 through the through hole 71 and starts to accumulate. The depressed insulating film 72 closes and seals the exhaust groove 70. Thereby, the sealed chamber 67 can be vacuum-sealed. However, since the storage chamber 69 itself is formed deeper than the exhaust groove 70, the insulating film 72 is stored in the bottom of the storage chamber 69. That is, the insulating film 72 is divided and the entire storage chamber 69 is not blocked. Accordingly, the storage chamber 69 and the through hole 71 can be kept in communication with each other.

  Next, after the sealing process is completed, a plating process for forming the feedthrough portion 68 in the through hole 71 which is a through hole is performed. That is, electrofeeding or electroless plating is performed to grow a conductive material so as to fill the storage chamber 69 and the through hole 71, thereby forming the feedthrough portion 68.

  Specifically, electroless plating is performed once, and then the through hole 71 and the storage chamber 69 are filled by electroplating, and unnecessary portions are removed to form the feedthrough portion 68. Electroless plating includes copper (copper sulfate aqueous solution + reducing agent), nickel (nickel sulfate aqueous solution or nickel chloride aqueous solution + reducing agent), gold (gold cyanide complex aqueous solution + reducing agent) and silver (silver cyanide). (Aqueous solution + reducing agent) or the like is used.

  Alternatively, a feed-through portion 68 is formed by applying a voltage to the end portion of the island 63b in contact with the storage chamber 69 from a voltage application wiring to the island 63b (not shown) and directly growing electroplating from the storage chamber 69 side. For example, the feedthrough portion 68 is formed by applying a negative voltage in a solution such as nickel sulfate or nickel chloride to grow a nickel plating product. Or the feedthrough part 68 is formed by applying a negative voltage in solutions, such as copper pyrophosphate and copper sulfate, and growing a copper plating thing. The plated product to be grown may be gold, rhodium, palladium, platinum or the like. In the case of gold, the plating solution used is a potassium dicyanogold (I) acid aqueous solution. In the case of rhodium, a solution of rhodium and sulfuric acid or rhodium and phosphoric acid is used. When the diamminepalladium (II) (PD (NH3) 2 (NO2) 2 aqueous solution is platinum, a solution of platinum and diaminonitrite is used.

The electronic device 50 shown in FIG. 18 can be manufactured by performing the said plating process. The vacuum package 60 of the electronic device 50 manufactured in this way can exhibit the same effects as the vacuum package 30 of the third embodiment described above. In other words, the vacuum package 60 is improved in the degree of vacuum in the sealed chamber 67 and is improved in performance. Moreover, since it is efficiently manufactured without man-hours, cost reduction is achieved. Furthermore, since one of the through holes 71 also serves as an exhaust hole, the durability of the upper lid substrate 61 is improved, the reliability is improved, and the size is reduced.
In addition, according to the electronic device 50 of the present embodiment, the vacuum package 60 in which the degree of vacuum of the sealed chamber 67 is improved is provided, so that the angular velocity can be detected with high sensitivity, and the reliability is improved. Can be planned. Moreover, size reduction and cost reduction can be achieved.

  In this embodiment, the electronic device 50 including the vacuum package described in the third embodiment is taken as an example. However, the present invention is not limited to this, and the vacuum package 1 described in the first embodiment and the second embodiment is used. , 20 may be used.

  The technical scope of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.

  For example, in the above-described embodiment, the element is the weight 51 as an example of the electronic device 50, and the angular velocity sensor that detects the angular velocity by exciting the weight 51 is taken as an example. However, the present invention is not limited to this case. For example, an acceleration sensor that simply detects acceleration without exciting the weight 51 may be used. Furthermore, although the element is the weight portion 51, if it is arranged in the sealed chamber 67 according to the device, a pressure sensor, an oscillator, a filter, or the like can be used as an electronic device.

It is sectional drawing of the vacuum package of 1st Embodiment which concerns on this invention. It is process drawing which showed the manufacturing method of the vacuum package shown in FIG. 1, Comprising: It is sectional drawing of a semiconductor substrate. FIG. 3 is a process diagram illustrating a manufacturing method of the vacuum package illustrated in FIG. 1, and is a diagram illustrating a state where an exhaust groove is formed from the state illustrated in FIG. 2. It is process drawing which showed the manufacturing method of the vacuum package shown in FIG. 1, Comprising: It is a figure which shows the state which formed the storage chamber from the state shown in FIG. FIG. 5 is a process diagram illustrating a manufacturing method of the vacuum package illustrated in FIG. 1, and is a cross-sectional view of an upper lid substrate. It is process drawing which showed the manufacturing method of the vacuum package shown in FIG. 1, Comprising: It is a figure which shows the state which formed the exhaust hole and the through-hole from the state shown in FIG. FIG. 2 is a process diagram illustrating a manufacturing method of the vacuum package shown in FIG. 1, in which an upper lid substrate in which exhaust holes and through holes are formed is joined to one surface of a semiconductor substrate in which exhaust grooves and storage chambers are formed. FIG. FIG. 8 is a process diagram illustrating a manufacturing method of the vacuum package illustrated in FIG. 1, and illustrates a state in which a frame and an island are formed on a semiconductor substrate from the state illustrated in FIG. 7. FIG. 6 is a process diagram illustrating a manufacturing method of the vacuum package illustrated in FIG. 1, and is a cross-sectional view of a lower lid substrate. It is process drawing which showed the manufacturing method of the vacuum package shown in FIG. 1, Comprising: It is a figure which shows the state which joined the lower lid board | substrate to the other surface of the semiconductor substrate. FIG. 11 is a process diagram illustrating a method of manufacturing the vacuum package illustrated in FIG. 1, and illustrates a state in which an insulating film is formed on the upper lid substrate from the state illustrated in FIG. 10. It is sectional drawing of the vacuum package of 2nd Embodiment which concerns on this invention. It is sectional drawing which shows the modification of the vacuum package shown in FIG. It is sectional drawing of the vacuum package of 3rd Embodiment which concerns on this invention. It is sectional drawing which shows the modification of the vacuum package shown in FIG. It is a disassembled perspective view of the electronic device of 4th Embodiment which concerns on this invention. FIG. 17 is a plan view of the SOI substrate of the electronic device shown in FIG. 16 as viewed from above while passing through the upper lid substrate. It is sectional drawing along the AA shown in FIG. It is process drawing which showed the manufacturing method of the electronic device shown in FIG. 18, Comprising: It is sectional drawing of a SOI substrate. FIG. 20 is a process diagram illustrating a method of manufacturing the electronic device illustrated in FIG. 18, and illustrates a state where an exhaust groove is formed on the silicon active layer from the state illustrated in FIG. 19. It is process drawing which showed the manufacturing method of the electronic device shown in FIG. 18, Comprising: It is a figure which shows the state which formed the storage chamber and the excitation gap from the state shown in FIG. It is process drawing which showed the manufacturing method of the electronic device shown in FIG. 18, Comprising: It is a figure which shows the state which formed the excitation gap on the silicon | silicone support layer from the state shown in FIG. FIG. 23 is a process diagram showing a method of manufacturing the electronic device shown in FIG. 18, and shows a state in which a frame, a weight part, and an upper part of an island are formed on the silicon support layer from the state shown in FIG. 22. FIG. 24 is a process diagram illustrating a method for manufacturing the electronic device illustrated in FIG. 18, and illustrates a state where an exposed BOX layer is removed from the state illustrated in FIG. 23. FIG. 19 is a process diagram illustrating a method of manufacturing the electronic device illustrated in FIG. 18, and is a cross-sectional view of an upper lid substrate. It is process drawing which showed the manufacturing method of the electronic device shown in FIG. 18, Comprising: It is a figure which shows the state which formed the through-hole from the state shown in FIG. It is process drawing which showed the manufacturing method of the electronic device shown in FIG. 18, Comprising: It is a figure which shows the state which formed the detection electrode from the state shown in FIG. FIG. 19 is a process diagram illustrating a method of manufacturing the electronic device illustrated in FIG. 18, illustrating a state where an upper lid substrate having a through hole is bonded to one surface of an SOI substrate having an exhaust groove and the like. . It is process drawing which showed the manufacturing method of the electronic device shown in FIG. 18, Comprising: It is a figure which shows the state which formed the flame | frame, the weight part, and the island in the SOI substrate from the state shown in FIG. FIG. 19 is a process diagram illustrating a method for manufacturing the electronic device illustrated in FIG. 18, and is a cross-sectional view of a lower lid substrate. It is process drawing which showed the manufacturing method of the electronic device shown in FIG. 18, Comprising: It is a figure which shows the state which formed the excitation electrode from the state shown in FIG. It is process drawing which showed the manufacturing method of the electronic device shown in FIG. 18, Comprising: It is a figure which shows the state which joined the lower lid board | substrate to the other surface of the semiconductor substrate. FIG. 33 is a process diagram showing the manufacturing method of the electronic device shown in FIG. 18, and shows a state where an insulating film is formed on the upper lid substrate from the state shown in FIG. 32. It is sectional drawing which showed an example of the conventional vacuum package.

Explanation of symbols

1, 20, 30, 40, 60 Vacuum package 2, 61 Upper lid substrate (first lid substrate)
3, 62 Lower lid substrate (second lid substrate)
4 Semiconductor substrate 4a, 63a Frame (frame part)
4b, 63b Island (support)
5, 67 Sealed chamber 6, 68 Feedthrough portion 10, 69 Storage chamber 11, 70 Exhaust groove 12, 71 Through hole 13, 72 Insulating film 14 Exhaust hole 50 Electronic device 51 Weight portion (element)
52 Beam
53 Excitation electrode 54 Detection electrode 63 SOI substrate (semiconductor substrate)

Claims (10)

An insulating first lid substrate and a second lid substrate arranged in parallel with each other at a predetermined interval, and a frame formed in a frame shape, joined in a state of being sandwiched between the two lid substrates. Manufacturing a vacuum package comprising: a semiconductor substrate having a portion, and a support portion provided in a sealed chamber surrounded by the frame portion and the first and second lid substrates and having both ends in contact with both lid substrates. A way to
A lid substrate forming step of forming an exhaust hole and a through hole in the first lid substrate;
When the first lid substrate is stacked on the semiconductor substrate, an exhaust groove is formed in the semiconductor substrate so as to communicate with the exhaust hole, and a storage chamber is formed in the semiconductor substrate so as to communicate with the through hole. A semiconductor substrate forming step;
Etching the semiconductor substrate only in a predetermined region, the sealed chamber communicating with the exhaust groove, the frame surrounding the periphery of the sealed chamber, and the support column provided in the sealed chamber and having the storage chamber on one end side And an etching process for forming the respective parts,
Joining the first lid substrate to one surface of the semiconductor substrate in which the exhaust groove and the storage chamber are formed, and joining the second lid substrate to the other surface of the semiconductor substrate; ,
A vacuum step of bringing the sealed chamber into a vacuum state via the exhaust groove and the exhaust hole;
A sealing step of vacuum-sealing the sealed chamber by forming an insulating film on the surface of the first lid substrate with a film thickness that closes the exhaust groove in a vacuum; and
A conductive material is plated so as to fill the storage chamber and the through hole, thereby forming a feedthrough portion in which one end side is electrically connected to the support column and the other end side is electrically connected to the outside. And a plating process to
By forming the storage chamber deeper than the exhaust groove during the semiconductor substrate forming step, a part of the insulating film falls into the storage chamber during the sealing step, and the insulating film is divided. A method for manufacturing a vacuum package, characterized in that:   2. The vacuum package manufacturing method according to claim 1, wherein, in the lid substrate forming step, the exhaust hole and the through hole are formed in a conical shape with a diameter gradually decreasing toward the semiconductor substrate. Method. An insulating first lid substrate and a second lid substrate arranged in parallel with each other at a predetermined interval, and a frame formed in a frame shape, joined in a state of being sandwiched between the two lid substrates. Manufacturing a vacuum package comprising: a semiconductor substrate having a portion, and a support portion provided in a sealed chamber surrounded by the frame portion and the first and second lid substrates and having both ends in contact with both lid substrates. A way to
A lid substrate forming step of forming an exhaust hole and a through hole in the first lid substrate and forming a storage chamber so as to communicate with the through hole;
A semiconductor substrate forming step of forming an exhaust groove in the semiconductor substrate so as to communicate with the exhaust hole when the first lid substrate is overlaid on the semiconductor substrate;
The semiconductor substrate is etched only in a predetermined region, the sealed chamber communicating with the exhaust groove, the frame portion surrounding the sealed chamber, and the support column provided in the sealed chamber and having one end in contact with the storage chamber And an etching process for forming each of
Joining the first lid substrate to one surface of the semiconductor substrate in which the exhaust groove is formed, and joining the second lid substrate to the other surface of the semiconductor substrate;
A vacuum step of bringing the sealed chamber into a vacuum state via the exhaust groove and the exhaust hole;
A sealing step of vacuum-sealing the sealed chamber by forming an insulating film on the surface of the first lid substrate with a film thickness that closes the exhaust groove in a vacuum; and
A conductive material is plated so as to fill the storage chamber and the through hole, thereby forming a feedthrough portion in which one end side is electrically connected to the support column and the other end side is electrically connected to the outside. And a plating process to
By forming the storage chamber deeper than the exhaust groove during the semiconductor substrate process, a part of the insulating film falls into the storage chamber during the sealing process, and the insulating film is divided. A manufacturing method of a vacuum package characterized by the above.   4. The vacuum package manufacturing method according to claim 3, wherein, in the lid substrate forming step, the exhaust hole and the through hole are formed in a conical shape with a diameter gradually decreasing toward the semiconductor substrate. Method.   5. The method of manufacturing a vacuum package according to claim 4, wherein, in the lid substrate forming step, the storage chamber is formed in a conical shape with a diameter gradually decreasing toward the through hole. . During the lid substrate forming step, the exhaust hole is also used as the through hole,
The vacuum package manufacturing method according to any one of claims 1 to 5, wherein, in the semiconductor substrate forming step, the exhaust groove is formed in the support portion so as to communicate with the storage chamber. .   The said 1st lid substrate, the said 2nd lid substrate, and the said semiconductor substrate are joined by anodic bonding or normal temperature bonding in the said joining process. A method for manufacturing a vacuum package according to 1.   A vacuum package manufactured by the method for manufacturing a vacuum package according to any one of claims 1 to 7. A vacuum package according to claim 8;
And an element provided in the sealed chamber. The element is a weight portion supported by the frame portion via a beam portion and disposed at a predetermined interval with respect to the first and second lid substrates,
An excitation electrode formed on the second lid substrate so as to face the weight portion in a state of being electrically connected to the support portion, and exciting the weight portion using electrostatic attraction;
Formed on the first lid substrate so as to be opposed to the weight portion in a state of being electrically connected to the column portion, and when the weight portion in a vibrating state receives an angular velocity and is displaced, The electronic device according to claim 9, further comprising a detection electrode that outputs a change in the distance as a change in capacitance.

Images