JP2012150029A - Vibration type transducer and method of manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify a manufacturing process of a vibration type transducer and simply improve the sensor performance.SOLUTION: A manufacturing method of a vibration type transducer includes a step in which a vibrator formation surface side of a first silicon substrate with the vibrator formed is joined to a second silicon substrate across an insulator film, a step in which the second silicon substrate is processed into a shell for covering the vibrator and functioning as an electrode for excitation of the vibrator or vibration frequency detection, and a step for vacuum sealing inside the shell.

Description

  The present invention relates to a vibratory transducer used for a transmitter or the like and a method for manufacturing the vibratory transducer.

  The vibration type transducer measures the applied physical quantity by detecting a change in the resonance frequency of the vibrator formed on the silicon substrate. Vibrating transducers are widely used in transmitters and the like as MEMS (Micro Electro Mechanical Systems) devices such as pressure sensors, acceleration sensors, angular velocity sensors, and resonators.

  FIG. 15 is a cross-sectional view illustrating the structure of a conventional vibration transducer. This figure is an example when the vibration type transducer is applied to a vibration type pressure sensor. As shown in this figure, the vibration type pressure sensor 300 includes a vibrator 310 formed on a silicon substrate 301 on which a diaphragm 302 is formed, and is covered with a shell 320. The inside of the shell 320 is a vacuum chamber having a high degree of vacuum in order to increase the mechanical Q value of the vibrator 310 and is sealed by a sealing material 330 made of an oxide film.

JP 2007-170843 A JP 2000-39371 A

  In the conventional vibration pressure sensor 300, a vibrator and a vacuum chamber surrounding the vibrator are formed of a multilayer film. For this reason, the manufacturing process is complicated, and it is difficult to adjust the vertical gap of the vibrator 310. As a result, the sensor characteristics are likely to vary, and the manufacturing cost is high.

  Further, in order to perform measurement in an environment with a high static pressure, it is necessary to increase the strength of the vacuum chamber by increasing the thickness of the shell 320 so that the shell 320 is not deformed. However, since the structure is formed by laminating thin films, it is difficult to increase the film thickness, and when the shell 320 is increased in thickness, a problem of film stress occurs. In Patent Document 2, it is described that a vacuum chamber of a pressure sensor is formed without using a multilayer film. The vacuum in this vacuum chamber is a vacuum as a reference pressure. For this reason, even if the technique described in Patent Document 2 is applied to the vibration pressure sensor as it is, the degree of vacuum required for vibration of the vibrator cannot be satisfied.

  Accordingly, an object of the present invention is to simplify the manufacturing process of a vibration type transducer and to easily improve the sensor performance.

  In order to solve the above-described problems, the method for manufacturing a vibration type transducer according to the first aspect of the present invention includes a second silicon substrate on which a vibrator is formed, and a second silicon wafer sandwiching an insulating film therebetween. Bonding the silicon substrate, processing the second silicon substrate into a shell that covers the vibrator and functions as an electrode for excitation or vibration frequency detection of the vibrator, And vacuum-sealing.

  Here, a vibrator forming step for forming a vibrator by forming a sacrificial layer and the vibrator layer in the first silicon substrate by diffusing impurities and etching the sacrificial layer. Further can be included.

  Alternatively, a recess is formed in the first silicon substrate, a sacrificial layer and a layer of the vibrator are formed in the recess by selective epitaxial growth, and the sacrificial layer is etched to form the vibrator. A vibrator forming step may be further included.

  Further, in the vibrator forming step, wiring for electrically connecting to the vibrator can be simultaneously formed from the vibrator layer.

  In addition, prior to the step of bonding the second silicon substrate with the insulating film interposed therebetween, a step of polishing the insulating film can be included. Further, the step of processing the shell can be performed by thinning the second silicon substrate. The method may further include a step of forming a convex shape on at least one of the opposing surfaces of the vibrator and the shell. In the step of vacuum-sealing the inside of the shell, a bonding prevention film can be formed on the vibrator and the shell.

  In order to solve the above-described problems, the vibratory transducer according to the second aspect of the present invention is manufactured by the above-described manufacturing method. Specifically, it can be a pressure sensor with a diaphragm or an absolute pressure sensor without a diaphragm.

  A first substrate on which a vibrator is formed; and a shell that covers the vibrator and functions as an electrode for exciting the vibrator or detecting a vibration frequency. As a vibratory transducer that is formed by processing a second substrate bonded to at least an insulating film with a vibrator formation surface of the substrate, and forms a vacuum chamber for increasing the mechanical Q of the vibrator. Also good.

  According to the present invention, the manufacturing process of the vibration type transducer can be simplified and the sensor performance can be easily improved.

It is a figure which shows the structure at the time of applying the vibration type transducer of this invention to a vibration type sensor chip. It is a figure which shows the outline | summary of the manufacturing method of the vibration type sensor chip of this embodiment. It is a figure explaining the detailed manufacturing procedure of a vibration type sensor chip. It is a figure explaining the detailed manufacturing procedure of a vibration type sensor chip. It is a figure which shows a sealing part. It is a figure which shows another example of P + layer and P ++ layer formation. It is a figure explaining the case where a bonded substrate is joined in the state where a beam is not formed. It is a figure which shows the example which forms a shell and wiring with another member. It is a figure explaining the example of joining prevention of a vibrator and a shell. It is a figure which shows the structure of the absolute pressure sensor which does not form a diaphragm. It is a figure explaining the example of a shape of a vibrator. It is a figure which shows the structure at the time of dividing a drive electrode and a detection electrode. It is a figure which shows the example at the time of using a piezoelectric drive as a drive method of a vibrator | oscillator. It is a figure explaining the method to detect with a piezoresistive element as a detection method of a vibration frequency. It is sectional drawing explaining the structure of the conventional vibration type transducer.

  Embodiments of the present invention will be described with reference to the drawings. FIG. 1A shows a structure when the vibration transducer of the present invention is applied to a vibration sensor chip. Moreover, FIG.1 (b) is sectional drawing in AA in Fig.1 (a).

  As shown in FIG. 1A, the vibration sensor chip 10 includes four vibrators 101 (101a, 101b, 101c, 101d) formed on a silicon substrate 100 having a diaphragm 110 formed on the back surface. Are covered with two shells 102 (102a, 102b). Hereinafter, when there is no need to distinguish between them, they are collectively referred to as the vibrator 101 and the shell 102.

  On the silicon substrate 100, as a terminal, a bonding pad 103a for connecting to the vibrator 101a through the wiring 104a, a bonding pad 103b for connecting to the vibrator 101b through the wiring 104b, and a vibration through the wiring 104c are used. Bonding pad 103c for connection to the child 101c, bonding pad 103d for connection to the vibrator 101d via the wiring 104d, bonding pad 103e for connection to the shell 102a via the wiring 104e, and shell via the wiring 104f A bonding pad 103f for connecting to 102b and a bonding pad 103g for determining the potential of the silicon substrate 100 are formed. Hereinafter, when there is no need to distinguish between them, they are collectively referred to as bonding pads 103 and wirings 104. The bonding pad 103 is made of Al, and the wiring 104 is a silicon wiring doped with impurities.

  As illustrated in FIG. 1B, a cavity 107 is formed around the vibrator 101 so as to be surrounded by the silicon substrate 100 and the shell 102. The cavity 107 is a vacuum chamber having a high degree of vacuum in order to increase the mechanical Q value of the vibrator 101. That is, by increasing the degree of vacuum in the vacuum chamber, the mechanical Q value of the vibrator 101 can be increased because the vibrator is stably excited at the resonance point and the loss of vibration energy is reduced. . The vibrator 101 is formed of silicon doped with impurities so as to be a conductor. The shell 102 is also formed of silicon doped with impurities so as to be a conductor.

  A predetermined amount of electrostatic gap is formed between the vibrator 101 and the shell 102, and the vibrator 101 and the shell 102 function as electrodes, and static electricity is generated by a potential difference between both electrodes applied from the bonding pad 103. An electromotive force is generated to excite the vibrator 101. Then, the vibration frequency of the excited vibrator 101 is detected by a change in capacitance between the vibrator 101 and the shell 102. The change in capacitance can be detected based on an electric signal taken out from the bonding pad 103.

  That is, when the pressure received by the silicon substrate 100 on which the vibrator 101 is formed changes, the distortion of the vibrator 101 changes, and the resonance frequency of the vibrator 101 changes. The vibration sensor chip 10 is a pressure sensor that measures pressure by detecting a change in the resonance frequency. However, various methods can be used for the excitation method of the vibrator 101 and the detection of the vibration frequency of the vibrator 101.

  FIG. 2 is a diagram illustrating an outline of a method for manufacturing the vibration sensor chip 10 of the present embodiment. As shown in FIG. 2B, N-type silicon is formed on the N-type silicon substrate 100 on which the doubly supported beam to be the P-type vibrator 101 shown in FIG. The bonded substrate 120 is bonded, and the bonded substrate 120 is processed to form the shell 102 as shown in FIG.

  The electrode of the shell 102 / vibrator 101, the wiring 104, and the substrate 100 are all formed of single crystal silicon, and the impurity concentration is increased in order to reduce the electrical resistance. The vibrator 101 is set to have a high impurity concentration in order to increase the selection ratio and strain of sacrificial layer etching for forming the cavity 107.

  As described above, the vibration type sensor chip 10 according to the present embodiment has a shell 102 formed of the bonded substrate 120 instead of the multilayer film laminated structure, thereby simplifying the manufacturing process and easily improving the sensor performance. Can be planned.

  The insulating film 130 is used as a bonding film on the silicon substrate 100 side, but is also used to adjust the electrostatic gap d. The insulating film also serves to electrically isolate the vibrator 101 and the shell 102.

  Substrate bonding can be performed by a bonding method in which surfaces are activated by plasma treatment or the like. Since the inside of the vibrator 101 and the bonded substrate 120 is activated when the substrates are joined, the vibrator 101 and the shell 102 may be joined. Therefore, as shown in FIG. A film 131 is attached to the inside to prevent the active surface from deactivating.

  The thickness of the shell 102 can be set to such a thickness that does not break when pressure is applied to the vibration sensor chip 10, and is set to a thickness that facilitates patterning.

  Next, a detailed manufacturing procedure of the vibration type sensor chip 10 of the present embodiment will be described with reference to FIGS. 3 and 4 are schematic sectional views showing the process flow of the vibration type sensor chip 10.

  First, as shown in FIG. 3A, an oxide film is formed on an N-type silicon substrate 100, and a mask M is formed by patterning the oxide film. Then, as shown in FIG. 3B, impurities (boron) are diffused to form a P + layer that becomes a sacrificial layer and generates a sub-vibrator gap, and a P ++ layer that becomes the vibrator 101 and the wiring 104.

  Next, as shown in FIG. 3C, the mask M used as a mask during impurity diffusion is removed, and an insulating film 130 made of an oxide film is formed and patterned. Polishing is also performed to remove the surface roughness of the insulating film 130 and steps. Then, a part of the P + layer formed by impurity diffusion is removed by etching to form the vibrator 101.

  Here, the insulating film 130 includes an etching mask for forming the vibrator 101 by sacrificial layer etching of the P + layer, a bonding film with the bonded substrate 120, adjustment of the vibrator upper gap, and the shell 102 and the vibrator 101. It functions as a step adjustment between the insulating film, the P ++ layer, and the surface of the silicon substrate 100.

  In addition, the polishing of the insulating film 130 before the bonding step is to form an uneven portion on the silicon substrate 100 due to impurity diffusion, and to reduce the uneven shape and surface roughness generated on the surface of the insulating film 130 formed on the surface. It is to do. Thereby, the film | membrane adhering in the cavity 107 at the time of subsequent sealing can be reduced, and it can be set as the surface state which can join the bonding board | substrate 120. FIG. The polishing method can be performed by polishing, CMP, or the like.

  At this time, a slight level difference can be left without being completely flattened, but it may be completely flattened. By completely flattening, the inside of the cavity 107 is sealed by bonding the bonded substrate 120 together. As a bonding method in this case, surface activated bonding under high vacuum can be employed, and vacuum sealing is performed simultaneously with bonding between the silicon substrate 100 and the bonded substrate 120.

  Adjustment of the thickness of the insulating film 130 for adjusting the vibrator upper gap can be easily performed by polishing and etching with hydrofluoric acid. By this treatment, the surface roughness that allows the bonded substrate 120 to be bonded to the insulating film 130 can be obtained.

  In the sacrificial layer etching of the P + layer, selective etching can be performed using an alkaline solution such as TMAH or hydrazine. The N-type silicon substrate 100 is anodically protected by electric field etching.

  The vibrator 101 is formed by the sacrificial layer etching, but the P + layer used as the wiring 104 is not etched by the insulating film 130 so that the vibrator 101 and the bonding pad 103 are electrically connected. Protect. The vibrator 101 can be formed by etching without sacrificing the sacrificial layer formed in the cavity 107 as in the conventional laminated film structure. Become.

  Next, as shown in FIG. 3D, a bonded substrate 120 which is an N-type silicon substrate is bonded using the insulating film 130 of the silicon substrate 100 as a bonding surface. Bonding substrate 120 can be bonded by a bonding method in which the surfaces are activated by plasma treatment or the like. After bonding, heat treatment is performed to perform processing for increasing the bonding strength. However, the bonding substrate 120 may be bonded by thermal bonding.

  The bonded substrate 120 can be composed of only single crystal silicon doped with a high impurity concentration, and does not form a pattern. With the orientation flat formed on the silicon wafer, the position relative to the silicon substrate 100 can be determined by adjusting the silicon crystal orientation to a predetermined orientation. Therefore, there is no need for fine alignment processing, and a simple process can be achieved.

  Note that another substrate may be sandwiched between the insulating film 130 and the bonded substrate 120, or a conductive film such as silicon may be formed. The insulating film 130 may be formed on the bonded substrate side 120 side.

  Next, as shown in FIG. 3E, the bonded bonded substrate 120 is ground and polished to a desired thickness. The thinning is performed so as to reduce the etching amount and facilitate processing when patterning the shell 102 later. Grinding and polishing can be easily performed by grinding. However, the grinding and polishing step can be omitted by using the bonded substrate 120 having a desired thickness. Further, the thinning may be performed by etching or blasting, or may be performed in combination.

  Next, as shown in FIG. 4A, the thinned bonded substrate 120 is patterned to form the shell 102 and the wiring 104 at the same time. The patterning for forming the shell 102 is preferably performed by dry etching so that water or chemicals do not enter the cavity 107 by wet etching. Thereby, the degree of vacuum in the shell 102 after sealing can be improved. The final thickness of the shell 102 can be adjusted by grinding and dry etching during shell patterning.

  Next, as shown in FIG. 4B, the cavity 107 is vacuum-sealed by CVD. The sealing step is necessary as a step for preventing the vibrator 101 and the shell 102 from joining. The surface is activated by plasma treatment or the like when the bonded substrate 120 is bonded. At this time, the portion where the vibrator 101 and the shell 102 which are not the bonding surface face each other is also activated and an active surface appears. For this reason, there exists a possibility that the vibrator | oscillator 101 and the shell 102 may join. In the present embodiment, the film 131 (see FIG. 2D) is attached to the activated surface of the vibrator 101 and the inner surface of the shell 102 by performing sealing by CVD in a process after the substrates are bonded, and deactivated. Let This prevents the vibrator 101 and the shell 102 from joining.

  Further, in the conventional manufacturing method of the laminated film structure, the passage connecting the inside and the outside of the cavity 107 needs to have a sufficient size as a sacrificial layer etching flow path. For this reason, more films adhere to the vibrator 101 at the time of sealing, and the influence on the tension of the vibrator 101 is increased. On the other hand, in this embodiment, since the bonded substrate 120 is bonded after the vibrator 101 is formed, the passage connecting the inside and the outside of the cavity 107 can be reduced, and the film 131 attached to the inside of the cavity 107 during sealing is reduced. can do. Thereby, the influence on the tension of the vibrator 101 can be reduced. In addition, the sealing hole 108 is provided in the edge part of the shell 102, as shown in sectional drawing 5 (b) of the location shown to BB in FIG. 5 (a).

  Next, as shown in FIG. 4C, the unnecessary sealing film is removed, and the insulating film 130 is patterned. Further, an Al film is formed and patterned to form the bonding pad 103.

  Finally, as shown in FIG. 4D, a concave portion is formed on the surface opposite to the surface on which the vibrator 101 is formed, and the diaphragm 110 is formed.

  As described above, the vibration type sensor chip 10 according to the present embodiment has a complicated laminated film structure, and the shell 102 is formed by the bonded substrate 120, so that many processes can be reduced and manufacturing can be easily performed. Cost can be reduced.

  Further, since the vibrator 101 can be formed before the cavity 107 is formed, the vibrator 101 can be easily formed and the yield is improved. Furthermore, when forming the electrodes of the vibrator 101 and the shell 102, the wiring 104 can be formed at the same time, and the process can be simplified. As a result, the manufacturing cost can be further reduced.

  Further, by forming the shell 102 with the bonded substrate 120 instead of the laminated film, the residual stress of the shell 102 can be reduced and the thickness of the shell 102 can be easily increased. Thereby, the breaking strength of the shell 102 can be increased, and the hydrostatic pressure resistance performance of the vibration type sensor chip 10 can be improved.

  Further, since the sacrificial layer etching is not performed after the cavity 107 is formed, a path connected to the cavity 107 can be reduced, and the film 131 attached to the cavity 107 at the time of sealing can be reduced. For this reason, since film adhesion to the vibrator 101 is reduced, the tension of the vibrator 101 can be kept high, and the vibration type sensor chip 10 in the high pressure range can be manufactured.

  In the above manufacturing procedure, as shown in FIG. 3A, boron as an impurity is diffused in the silicon substrate 100 to form the P + layer and the P ++ layer. As shown in FIG. 6B, the silicon substrate 100 is etched to form a recess and the P + layer and the P ++ layer are backfilled as shown in FIG. 6B. Also good. FIG. 6C shows the formation of the P ++ layer, and FIG. 6D shows the formation of the P ++ layer. However, the P + layer and the P ++ layer may be formed by selective epitaxial growth without etching the silicon substrate 100 and without forming a recess.

  The present invention is not limited to the manufacturing method and structure described above, and various modifications can be applied. For example, in the above example, the bonded substrate 120 is bonded to the silicon substrate 100 on which the beam to be the vibrator 101 is formed via the insulating film 130, but no beam is formed as shown in FIG. The bonded substrate 120 may be bonded in a state.

  At this time, after forming a pattern to form the vibrator 101 by etching, the silicon substrate 100 and the bonded substrate 120 are bonded to each other without forming a beam, and the shell 102 is formed. Then, FIG. As shown, the sacrificial layer 134 is etched in the state of the bonded substrate. When the beam is formed in such a procedure, the pattern edge portion of the insulating film 130 is not damaged by etching, and it becomes easy to firmly bond the bonded substrate 120 to the pattern edge portion of the insulating film 130.

  In the above example, an N-type silicon substrate is used as the bonded substrate 120, but a P-type silicon substrate may be used. The insulation resistance between the vibrator 101 and the shell 102 is easier when the N-type silicon substrate is used, but the wiring resistance can be reduced more easily and the contact resistance with the bonding pad 103 is easier with the P-type silicon substrate. Can be made smaller.

  In the above example, the shell 102 and the wiring 104 of the shell 102 are formed from the bonded substrate 120. However, as shown in FIGS. 8A and 8B, the wiring 104 is formed from another member. You may do it. For example, when the thickness of the shell 102 is set to be thick, there is a possibility that a problem may occur due to a large step when the bonding pad 103 or the like is formed. In such a case, by forming the wiring 104 with a separate member, the level difference can be reduced and easy patterning can be performed. Alternatively, the thickness may be adjusted by, for example, etching part or all of the wiring 104 after patterning the shell 102 and the wiring 104 at the same time. In this case, the wiring resistance is considered.

  As described above, the surface is activated by plasma treatment or the like at the time of substrate bonding. At this time, the activation process is also performed on a portion where the vibrator 101 and the shell 102 which are not the bonding surface face each other, and an active surface appears. . This active surface is deactivated by a film formed at the time of sealing, but there is a possibility that the vibrator 101 and the shell 102 are bonded before sealing.

  Therefore, the convex shape 136 and the convex shape 138 are formed on the shell 102 or the vibrator 101 as shown in FIGS. 9A and 9B, or the activation process is performed as shown in FIG. Even if it is difficult to bond, it is effective to form a bonding preventing film 132 that is difficult to bond. If measures for preventing the bonding between the vibrator 101 and the shell 102 are taken, the sealing step by CVD film formation can be omitted.

  Although it is sufficient that the convex shape is formed at a part of one of the shell 102 and the vibrator 101, there is a possibility that the sensor performance may be affected by a change in the resonance frequency or strain of the vibrator 101. Therefore, formation on the shell 102 side is desirable.

  As the bonding prevention film 132, silicon carbide, DLC (diamond-like carbon), or the like can be used. When the film is formed on the vibrator 101 side, it is necessary to consider the residual stress of the bonding prevention film 132, appropriate pattern formation, formation area, and the like for the reasons described above.

  There are no restrictions on the number of vibrators 101 and shells arranged in one chip. By changing these numbers, it is possible to reduce the size and improve the accuracy of the vibration type sensor chip. FIG. 10 shows a case where there are two vibrators 101 and one shell 102, and one vibrator 101 is used as a reference vibrator to improve measurement accuracy. The shape of the vibrator 101 may be a double-ended I-shape as shown in FIG. 11 (a), an H-shape as shown in FIG. 11 (b), or as shown in FIG. 11 (c). It is good also as a cantilever. In FIG. 11B, a recess 140 after sacrificial layer etching is formed around the H-type vibrator 1.

  Furthermore, the vibration type transducer of the present invention can also be applied to an absolute pressure sensor that does not form a diaphragm, and FIG. 10 shows a structural example when the vibration type transducer is applied to an absolute pressure sensor 20 that does not form a diaphragm. ing.

  In the above example, the electrostatic drive for exciting the vibrator 101 and the detection of the electrostatic capacity for measuring the change of the vibration frequency are performed by the same electrode, but the drive electrode and the detection electrode are separated. It may be. In this case, as shown in FIG. 12, either the detection electrode or the drive electrode 142 is disposed under the vibrator 101, and the shell 102 is the other electrode.

  Further, methods other than electrostatic drive and capacitance detection methods may be used as the method for driving the vibrator 101 and the method for detecting the vibration frequency. As another driving method of the vibrator 101, for example, a piezoelectric driving method can be used. When using piezoelectric driving, as shown in FIG. 13, the piezoelectric element 144 to which the wiring 145 is connected may be disposed at the base portion of the vibrator 101. In this case, the shell 102 serves as an electrode for detecting capacitance.

  As another method of detecting the vibration frequency, for example, a method of detecting by a piezoresistive element can be used. In this case, as shown in FIG. 14, the piezoresistive element 146 to which the wiring 147 is connected may be disposed at the base portion of the vibrator 101. In this case, the shell 102 becomes an electrode for electrostatic driving. Further, a combination of a piezoelectric drive and a detection method based on a change in capacitance, or a combination of a detection method using an electrostatic drive and a piezoresistive element may be used.

  The vibratory transducer of the present invention can be widely used as a MEMS (Micro Electro Mechanical Systems) device such as a pressure sensor, an acceleration sensor, an angular velocity sensor, and a resonator. As described above, according to the present invention, the manufacturing process of the vibration type transducer can be simplified and the sensor performance can be easily improved.

DESCRIPTION OF SYMBOLS 10 ... Vibration type sensor chip, 20 ... Absolute pressure sensor, 100 ... Silicon substrate, 101 ... Vibrator, 102 ... Shell, 103 ... Bonding pad, 104 ... Wiring, 107 ... Cavity, 108 ... Sealing hole, 110 ... Diaphragm , 120 ... bonded substrate, 130 ... insulating film, 131 ... film, 132 ... anti-bonding film, 134 ... sacrificial layer, 136 ... convex shape, 138 ... convex shape, 140 ... concave portion, 142 ... electrode, 144 ... piezoelectric element, 145: Wiring, 146: Piezoresistive element, 147: Wiring, 300: Vibration pressure sensor, 301: Silicon substrate, 302: Diaphragm, 310 ... Vibrator, 320 ... Shell, 330 ... Sealing material

Claims (12)

Bonding a second silicon substrate with at least an insulating film on the vibrator forming surface side of the first silicon substrate on which the vibrator is formed;
Processing the second silicon substrate into a shell that covers the vibrator and functions as an electrode for excitation or vibration frequency detection of the vibrator;
And a step of vacuum-sealing the inside of the shell.   And further including a vibrator forming step of forming a sacrificial layer and the vibrator layer by diffusing impurities in the first silicon substrate, and etching the sacrificial layer to form the vibrator. The method of manufacturing a vibration type transducer according to claim 1.   The method further includes a vibrator forming step of forming the vibrator by forming a sacrificial layer and the vibrator layer on the first silicon substrate by selective epitaxial growth and etching the sacrificial layer. A manufacturing method of the vibration type transducer according to claim 1.   4. The method of manufacturing a vibratory transducer according to claim 2, wherein in the vibrator forming step, wiring for electrically connecting to the vibrator is simultaneously formed from the vibrator layer.   5. The method of manufacturing a vibration transducer according to claim 1, further comprising a step of polishing the insulating film prior to a step of bonding the second silicon substrate with the insulating film interposed therebetween. Method. The step of processing into the shell comprises
6. The method of manufacturing a vibration type transducer according to claim 1, wherein the second silicon substrate is thinned.   The method for manufacturing a vibration transducer according to claim 1, further comprising a step of forming a convex shape on at least one of the opposing surfaces of the vibrator and the shell.   8. The vibration transducer according to claim 1, wherein in the step of vacuum-sealing the inside of the shell, a bonding prevention film is formed between the vibrator and the shell. Production method.   A vibratory transducer manufactured by the manufacturing method according to claim 1. A first substrate on which a vibrator is formed;
A shell that covers the vibrator and functions as an electrode for excitation or vibration frequency detection of the vibrator;
The shell is formed by processing a second substrate that is bonded to the vibrator formation surface of the first substrate with at least an insulating film interposed therebetween, and has a vacuum chamber for increasing the mechanical Q of the vibrator. A vibration transducer characterized by being formed.   11. The vibration type transducer according to claim 9, wherein the vibration type transducer is a pressure sensor having a diaphragm.   The vibratory transducer according to claim 9 or 10, wherein the transducer is an absolute pressure sensor not provided with a diaphragm.