JP4587727B2 - Piezoelectric vibrator storage package and piezoelectric device - Google Patents

Description

  The present invention relates to a piezoelectric vibrator housing package and a piezoelectric device that house a piezoelectric vibrator such as a crystal vibrator inside an insulating base, and in particular, the piezoelectric vibrator together with other electronic components such as a semiconductor element. The present invention relates to a piezoelectric vibrator housing package for hermetically housing and a piezoelectric device using the piezoelectric vibrator housing package.

  In an electronic device such as a communication device such as a mobile phone or a car phone, or an information device such as a computer or an IC card, a piezoelectric vibrator such as a crystal vibrator is used as a reference for frequency and time. Hereinafter, piezoelectric devices that are hermetically housed in a package) are also widely used.

  As such a piezoelectric device, in recent years, an AT-cut crystal resonator and a tuning-fork crystal resonator are housed in one package as a piezoelectric resonator, and the package is used for controlling a semiconductor element or the like having an oscillation circuit. There has been proposed a piezoelectric device having a plurality of oscillation sources, that is, a so-called dual clock module type piezoelectric device having a structure in which the electronic components are mounted and housed.

  Note that the AT-cut crystal resonator functions as an oscillation source for a main clock in, for example, the MHz band, and the tuning fork crystal resonator functions as a sub-clock (for example, for standby operation) in, for example, the kHz band.

  FIG. 3A is a plan view schematically showing the configuration of a conventional piezoelectric device, and FIG. 3B is a cross-sectional view thereof. In the figure, 51 is a substrate, 52 is a semiconductor element having an oscillation circuit for controlling the oscillation frequency of the piezoelectric vibrator, 53 is an AT-cut crystal vibrator as a piezoelectric vibrator, and 54 is a tuning fork as a piezoelectric vibrator. Type crystal resonator. The semiconductor element 52 having an oscillation circuit is fixed on the substrate 51 with a conductive adhesive, and is further electrically connected to the connection pad 57 by an electrical connection means such as a bonding wire 56, and is formed on the lower surface of the outer peripheral portion of the substrate 51. The input / output terminal 60 is electrically connected.

  Further, the AT-cut crystal resonator 53 and the tuning-fork crystal resonator 54 that oscillate at a predetermined frequency are respectively joined to the mounting portion in the recess 55 formed on the upper surface of the substrate 51, and the recess 55 is formed on the upper surface of the base 51. The AT-cut crystal unit 53 and the tuning-fork type crystal unit 54 are hermetically sealed by bonding the lid 62 and the like to the sealing metallization layer 58 formed so as to be surrounded by a brazing material such as solder. The device is configured.

  Such a piezoelectric device is mounted, for example, by connecting an input / output terminal 60 to a predetermined position of an external circuit board 61 that constitutes an electronic device such as a mobile phone via solder or the like, and an oscillation source for a main clock. A reference signal such as a communication frequency is transmitted from the AT-cut crystal unit 53 to the electric circuit of the electronic device. Further, when the main power supply of the electronic device is turned off, the sub-clock (standby operation) tuning-fork type crystal resonator 54 continues to operate, and functions such as, for example, keeping time and timer.

Reference numeral 59 denotes an electronic component such as a capacitive element or an inductor element that forms an oscillation circuit together with the piezoelectric vibrators 53 and 54 and the semiconductor element 52.
Japanese Patent Laid-Open No. 6-232631

  However, when a plurality of piezoelectric vibrators 53 and 54 and another electronic component 59 such as the semiconductor element 52 are mounted and housed in one package in this way, the package mounting area increases, so that the outer shape of the package is increased. However, there is a problem that it is difficult to reduce the size of the information communication device.

  Further, the piezoelectric vibrators such as the AT-cut type crystal vibrator 53 and the tuning-fork type crystal vibrator 54 accommodated in the concave portion 55 of the piezoelectric device are placed in the concave portion 55 for stable oscillation at a specific frequency during long-term use. Generally, it is vacuum-sealed, and a sealing metallization layer 58 for hermetically sealing the piezoelectric vibrators 53 and 54 must be provided in addition to the mounting portion of the semiconductor element 52 on the substrate 51. Since their mounting area is increased, the outer shape of the package is further increased, which makes it difficult to reduce the size of the information communication device.

  In particular, when the AT cut type crystal resonator 53 and the tuning fork type crystal resonator 54 are simultaneously mounted on the substrate 51 as in the dual clock module type piezoelectric device, the piezoelectric device becomes very large.

  In addition, when the semiconductor element 52, the piezoelectric vibrator such as the AT-cut type crystal vibrator 53 and the tuning fork type crystal vibrator 54, and the electronic component 59 are simultaneously mounted and accommodated on the substrate 51, the piezoelectric vibrator includes, for example, an AT. The cut crystal unit 53 functions at a high frequency in the MHz band, and the tuning fork type crystal unit 54 functions at a relatively low frequency in, for example, the kHz band. There is a problem in that electromagnetic waves generated in the mounted piezoelectric vibrators 53 and 54 adversely affect the oscillation frequency characteristics of the piezoelectric vibrators 53 and 54, respectively.

  Further, in the electronic component 59 such as the semiconductor element 52, the capacitive element, and the inductor element, an oscillation circuit is formed together with the piezoelectric vibrators 53 and 54 accommodated in the recess 55, and electromagnetic waves generated in the respective electronic components are formed. However, there is a problem that the oscillation frequency characteristics of the piezoelectric vibrators 53 and 54 are adversely affected.

  Further, the external circuit board 61 to which the input / output terminal 60 disposed on the lower surface of the outer peripheral portion of the substrate 51 of the piezoelectric device is connected is generally made of a resin made of glass epoxy or the like. Since the coefficient of thermal expansion is different from that of ceramics (alumina ceramics, etc.) frequently used, the input / output is arranged on the outer peripheral portion of the lower surface of the substrate 51 by the temperature cycle after connection as the outer dimension of the substrate 51 becomes larger. Thermal stress is likely to occur between the terminal 60 and the connection pad formed on the main surface of the external circuit board 61, and this thermal stress causes problems such as solder cracks and disconnection at the connection portion of the input / output terminal 60. There was a problem that it occurred.

  The present invention has been devised in view of the problems of the prior art, and the object thereof is to enable downsizing even if the piezoelectric vibrator is housed together with other electronic components such as a semiconductor element, and An object of the present invention is to provide a piezoelectric vibrator housing package and a piezoelectric device that are excellent in characteristics such as an oscillation frequency characteristic of a piezoelectric vibrator and that are excellent in reliability of electrical connection to an external electric circuit or the like.

The piezoelectric vibrator housing package according to the present invention includes an insulating base having three recesses formed on the upper surface, a frame formed around the three recesses on the upper surface of the insulating base, and the frame. A wiring conductor formed from the inner side of the insulating base to the outer surface of the insulating base, a porous powder made of porous ceramics, sol-gel glass or silica gel, and a resin containing metal powder , and the three concave portions formed on the upper surface of the insulating base. One of the three recesses, and one of the AT-cut crystal resonator and the tuning-fork crystal resonator that is a piezoelectric resonator is connected to the other of the three recesses. The other is accommodated in one, the electronic component is accommodated in the other, and a semiconductor element is mounted on the upper surface of the lid.

  In the piezoelectric vibrator housing package according to the present invention, preferably, the three concave portions are formed in a line, and the piezoelectric vibrators are housed in the concave portions located at both ends, respectively, and the central portion is located in the central portion. The electronic component is accommodated in the recess.

  The piezoelectric device of the present invention includes the above-described piezoelectric vibrator housing package of the present invention, the piezoelectric vibrator housed in the recess and having an electrode electrically connected to the wiring conductor, and housed in the recess. The electronic component having an electrode electrically connected to the wiring conductor, and the semiconductor element mounted on the upper surface of the lid and having the electrode electrically connected to the wiring conductor. It is characterized by being.

According to the piezoelectric vibrator housing package of the present invention, the insulating base having three recesses formed on the upper surface, the frame formed around the three recesses on the upper surface of the insulating base, and the frame A wiring conductor formed from the inner side of the insulating substrate to the outer surface of the insulating substrate, a porous powder made of porous ceramics, sol-gel glass or silica gel, and a resin containing metal powder , and the upper surface of the insulating substrate is closed with the three recesses And one of the three recesses has one of an AT-cut crystal resonator and a tuning-fork crystal resonator as one of the three recesses. The other is housed, and the electronic component is housed in the other, and the semiconductor element is mounted on the upper surface of the lid. Therefore, the piezoelectric vibrator and the semiconductor element are moved up and down at regular intervals. Line up Since it can be accommodated, for example, in the plane area of the insulating base that is the minimum necessary to mount the semiconductor element, not only the semiconductor element but also the piezoelectric vibrator and the electronic component can be arranged vertically and accommodated, The piezoelectric vibrator housing package can be reduced in size.

  In addition, since the planar area of the insulating base is reduced, even when a thermal stress is generated between the external circuit board and the insulating base when the piezoelectric vibrator housing package is connected to the external circuit board, the mounting area is small. Because it is small, it can reduce the stress due to the dimensional change of the external circuit board, effectively preventing the occurrence of defects such as solder cracks and disconnection at the connection part between the piezoelectric vibrator housing package and the external circuit board. The connection to the circuit board can be maintained well over a long period of time.

  Furthermore, the space for housing the piezoelectric vibrator and electronic components and the space on which the semiconductor element is mounted can be effectively electromagnetically blocked by the lid, and electromagnetic waves generated by the semiconductor element or the like are applied to the piezoelectric vibrator. An adverse effect can be effectively prevented, and the characteristics of the piezoelectric vibrator (for example, the oscillation frequency characteristics of the piezoelectric vibrator) can be maintained well.

In addition, the two piezoelectric vibrators and the electronic parts are divided and accommodated in three concave parts, respectively, and each concave part is closed with a lid, so that the two piezoelectric vibrators and the electronic parts are more effective for the lid. The electromagnetic waves generated by the electronic components can adversely affect the piezoelectric vibrator, and the two piezoelectric vibrators can interfere with each other due to the vibration and electromagnetic waves interfering with each other. It is possible to effectively prevent this and maintain the characteristics of the piezoelectric vibrator (for example, the oscillation frequency characteristics of the piezoelectric vibrator) well.

  In the piezoelectric vibrator housing package of the present invention, preferably, the three concave portions are formed in a line, and the piezoelectric vibrators are accommodated in the concave portions located at both ends, respectively. Since the electronic parts are accommodated, the piezoelectric vibrators can be separated from each other with a large space by the space for accommodating the electronic parts in the central recess, and the electromagnetic waves generated in the piezoelectric vibrators respectively can be separated. It is possible to more effectively prevent adverse effects on the oscillation frequency characteristics of the piezoelectric vibrator.

Further, in the piezoelectric vibrator housing package of the present invention, before Symbol piezoelectric vibrator, one is AT-cut quartz resonator, since the other is a tuning fork type quartz oscillator, so-called dual-clock module type piezoelectric device The electronic device such as a mobile phone in which such a piezoelectric device is used as a component can be effectively downsized. Furthermore, since the wiring path can be shortened by downsizing, the power consumption can be reduced, and the power consumption of the electronic device can be effectively reduced.

  According to the piezoelectric device of the present invention, the piezoelectric vibrator housing package having the above-described configuration, the piezoelectric vibrator housed in the recess and the electrode electrically connected to the wiring conductor, and housed in the recess. And an electronic component in which the electrode is electrically connected to the wiring conductor and a semiconductor element mounted on the upper surface of the lid and the electrode is electrically connected to the wiring conductor. In addition, the piezoelectric vibrator can be excellent in characteristics such as the oscillation frequency characteristics, and can be excellent in reliability of electrical connection to an external electric circuit or the like.

  Next, a piezoelectric vibrator housing package and a piezoelectric device according to the present invention will be described with reference to the accompanying drawings. FIG. 1A is a plan view showing an example of an embodiment of a piezoelectric vibrator housing package and a piezoelectric device according to the present invention, and FIG. 1B is a cross-sectional view thereof.

  1 (a) and 1 (b), 1 is an insulating substrate, 2 is an AT-cut crystal resonator as a piezoelectric resonator, 3 is a tuning fork crystal resonator as a piezoelectric resonator, 4 is an electronic component, A frame part, 6 is a wiring conductor formed from the inside of the frame part to the outer surface of the insulating substrate 1, 7 is a lid, and 8 is a semiconductor element.

  The insulating base 1, the wiring conductor 6, the frame portion 10, and the lid body 7 mainly constitute a package for housing a piezoelectric element of the present invention, and a piezoelectric vibrator is provided in three recesses 5 formed on the upper surface of the insulating base 1. The insulating base 1 is accommodated by housing a certain AT-cut type crystal resonator 2, tuning fork type crystal resonator 3, and electronic component 4 and attaching a lid 7 so as to close the concave portion 5 on the upper surface of the insulating base 1. The AT-cut crystal resonator 2, tuning fork crystal resonator 3, and electronic component 4 are housed in an airtight manner inside each container formed by the recesses 5 and the lid body 7. By mounting the semiconductor element 8, the piezoelectric device of the present invention is basically formed. This piezoelectric device is used by being mounted on an external circuit board (not shown) constituting an electronic device such as a mobile phone. The piezoelectric vibrators 2 and 3 are accommodated in two of the three recesses 5, and the electronic component 4 is accommodated in the other recess 5.

  The insulating substrate 1 has three concave portions 5 for accommodating the piezoelectric vibrators 2 and 3 and the electronic component 4 on the upper surface, and the concave portion 5 and the lid body 7 constitute a piezoelectric vibrator (AT-cut crystal vibrator 2). , Tuning fork type crystal resonator 3 and the like) and electronic component 4 can be hermetically sealed.

  Here, the insulating substrate 1 is made of an aluminum oxide sintered body (alumina ceramics), an aluminum nitride sintered body, a mullite sintered body, ceramics such as glass ceramics, or a resin-based material such as glass epoxy resin. It is made of an insulating material and has, for example, a rectangular parallelepiped shape having a side length of about 5 to 20 mm and a thickness of about 1 to 5 mm.

  If the insulating base 1 is made of, for example, an aluminum oxide sintered body, it is manufactured as follows. First, an appropriate organic vanida, solvent, plasticizer, etc. are added to and mixed with raw material powders such as aluminum oxide, silicon oxide, magnesium oxide, calcium oxide, etc. to form a mud, which is a well-known doctor blade method or calendar roll method. Etc. to form a plurality of ceramic green sheets. After that, the ceramic green sheet is appropriately punched to form a square plate and three square punched portions formed in the center, and the square plate is located in the lower layer. By laminating up and down so that the one having a rectangular punched portion is located in the upper layer, a laminated body having three concave portions 5 on the upper surface is formed, and the laminated body is baked at a high temperature (about 1600 ° C.) Produced.

  In this case, the strip-like portion remaining between the punched portions of the green sheet becomes a wall that separates the recesses 5.

  Alternatively, a large recess may be formed in the central portion of the insulating base 1, and a wall material may be attached to the bottom surface of the large recess so as to be divided into three recesses 5.

  Preferably, vias and side conductors that are joined to the lid body 7 are formed inside and on the surface of the wall that partitions the plurality of recesses 5. Accordingly, the heat generated from the semiconductor element 8 mounted on the lid 7 is formed on the lid 7, the via formed in the wall separating the plurality of recesses 5, and the side surface formed on the wall separating the plurality of recesses 5. The conductor can be dissipated well, the semiconductor element 8 can be operated satisfactorily for a long time, and the piezoelectric vibrators 2 and 3 and the electronic component 4 accommodated in the plurality of recesses 5 can be connected by the vias and the side conductors. It is possible to cut off electromagnetically well. More preferably, the wall separating the plurality of recesses 5 is made of metal. Thereby, the heat dissipation of the heat generated from the semiconductor element 8 and the effect of electromagnetic shielding are further improved.

  A lid 7 is attached to the upper surface of the insulating base 1 so as to close the three recesses 5. The lid 7 functions to seal the piezoelectric vibrators 2 and 3 and the electronic component 4 in an airtight manner by closing the recess 5. The lid 7 also functions as a mounting portion on which the semiconductor element 8 is mounted on the upper surface, and also functions as a heat radiating plate for releasing the heat generated from the semiconductor element 8 to the outside.

  Attachment to the upper surface of the recessed part 5 of the cover body 7 can be performed by joining via joining materials, such as a brazing material, solder, glass, an organic resin adhesive, etc., for example.

A semiconductor element 8 is mounted on the upper surface of the lid body 7. The semiconductor element 8 is, for example, a control element having an oscillation circuit for controlling the oscillation frequency of a crystal oscillator for a real-time clock, and is attached to the upper surface of the lid body 7 with solder, an adhesive, or the like. .

  A frame portion 10 is formed on the upper surface of the insulating base 1 so as to surround the entire three concave portions 5. The frame portion 10 may be bonded to the upper surface of the insulating base 1 with an adhesive or the like, or may be formed integrally with the insulating base 1. In addition, the frame part 10 is formed outside the part to which the lid body 7 is attached.

  The frame portion 10 functions as a dam member that prevents the sealing resin 9 from flowing out to the side surface or the like of the insulating base 1 when the semiconductor element 8 is covered with the sealing resin 9. It functions as an insulator or the like for drawing the wiring conductor 6 to be formed. By sealing the semiconductor element 8 with the sealing resin 9, durability against external temperature and humidity can be improved, and a structure with further excellent long-term reliability can be obtained.

The semiconductor element 8 may be hermetically sealed by attaching a lid (not shown) made of metal, ceramic material, resin, or the like to the upper surface of the frame portion 10.

  A wiring conductor 6 is formed from the inner side of the frame portion 10 to the outer surface such as the lower surface and the side surface of the insulating base 1. The wiring conductor 6 electrically connects the semiconductor element 8 mounted on the upper surface of the lid 7, the piezoelectric vibrators 2 and 3 and the electronic component 4 accommodated in the recess 5, or connects them to the insulating base 1. It functions as a conductive path that leads to the outer surface and is electrically connected to the external circuit board.

  A portion of the wiring conductor 6 led out to the outer surface of the insulating base 1 (a portion exposed in the outer peripheral portion of the lower surface of the insulating base 1 in the example of FIG. 1) is soldered or electrically conductive to an electric circuit of the external circuit board. By bonding through a conductive bonding material such as an adhesive, the piezoelectric device is electrically and mechanically connected to the external circuit board, and the wiring conductor 6 is electrically connected to the electric circuit of the external circuit board.

  Then, the piezoelectric vibrators 2 and 3 and the electronic component 4 are accommodated in the recess 5 of the insulating base 1, and the respective electrodes are connected to the wiring conductor 6 via a conductive connecting material (not shown) such as solder or bonding wire. After electrically connecting, the recess 5 is closed with the lid 7, and then the semiconductor element 8 is mounted on the upper surface of the lid 7, and the electrode of the semiconductor element 8 is connected to the exposed portion of the wiring conductor 6 via a bonding wire or the like. The piezoelectric device is manufactured by connecting and sealing the semiconductor element 8 with a sealing resin 9 as necessary. In this case, a resonance circuit is formed between the piezoelectric vibrators 2 and 3, the electronic component 4, the semiconductor element 8, and the like.

  The wiring conductor 6 may be formed on the upper surface of the insulating base 1 inside the recess 5, and as shown in FIG. 1, a step is formed on the inner peripheral surface of the frame portion 10, and the upper surface of the step is formed. It may be formed.

  With the above configuration, in the piezoelectric vibrator housing package and the piezoelectric device according to the present invention, the three concave portions 5 are formed in a line, and the AT cuts that are piezoelectric vibrators are formed in the concave portions 5 located at both ends, respectively. Since the quartz crystal resonator 2 and the tuning fork crystal resonator 3 are accommodated, and the electronic component 4 is accommodated in the recess 5 located in the center, for example, the insulating substrate 1 that is the minimum necessary for mounting the semiconductor element 8 is used. In this plane area, not only the semiconductor element 8 but also the piezoelectric vibrators 2 and 3 and the electronic component 4 can be housed, and the piezoelectric vibrator housing package can be downsized.

  Further, since the planar area of the insulating base 1 is reduced, even if a thermal stress is generated between the external circuit board and the insulating base 1 when the piezoelectric vibrator housing package is connected to the external circuit board, the mounting region Since the area is small, stress due to dimensional changes of the external circuit board can be reduced, and it is possible to effectively prevent defects such as solder cracks and disconnections at the connection between the piezoelectric vibrator housing package and the external circuit board. Thus, the connection to the external circuit board can be maintained well over a long period of time.

Furthermore, the space for housing the piezoelectric vibrators 2 and 3 and the electronic component 4 and the space in which the semiconductor element 8 is mounted can be effectively electromagnetically cut off by the lid body 7. 4 effectively prevents adverse effects of electromagnetic waves generated by the piezoelectric vibrators 2 and 3 on characteristics of the piezoelectric vibrators 2 and 3 (for example, piezoelectric vibrations of the AT-cut crystal vibrator 2 and the tuning-fork crystal vibrator 3). The oscillation frequency characteristics of the child can be maintained well. The lid 7 is a material formed by containing and dispersing porous powder and metal powder made of porous ceramics, sol-gel glass or silica gel in a resin in order to make the above-described electromagnetic shielding effective. Form.

The piezoelectric vibrator is AT-cut quartz resonator 2 and the tuning-fork crystal unit 3 as above described, functions for oscillating a reference signal such as frequency, such as an oscillation to the time and communication at a predetermined frequency Make. This reference signal is supplied to an external electric circuit via the wiring conductor 6. In addition, a current required for operating the crystal resonators 2 and 3 and the semiconductor element 8 is supplied from the external electric circuit into the piezoelectric device. The connection between the piezoelectric vibrators 2 and 3 and the wiring conductor 6 is performed by bonding with a conductive adhesive or the like.

  The electronic component 4 is, for example, a surface-mounted passive element such as a capacitive element (a known ceramic capacitor or the like) or an inductor element, and forms an oscillation circuit together with the piezoelectric vibrators 2 and 3 and the semiconductor element 8. Mounting in the recess 5 located at the center of the electronic component 4 is performed, for example, by electrically and mechanically connecting the electrode to the exposed portion of the wiring conductor 6 via solder or the like.

In the piezoelectric vibrator storing package and the piezoelectric device of the present invention, the piezoelectric vibrator is AT-cut quartz resonator 2 and the tuning-fork type crystal vibrating piece 3. In this case, a resonance circuit is formed between the AT-cut crystal resonator 2, the tuning fork crystal resonator 3, the electronic component 4, and the semiconductor element 8, and a so-called dual clock module type piezoelectric device is formed.

  The AT-cut crystal resonator 2 functions as a main clock oscillation source in the MHz band, for example, and the tuning fork crystal resonator 3 functions as a sub-clock (for example, standby operation) in the KHz band, for example.

  When the piezoelectric device of the present invention is a dual clock module type in which the AT cut type crystal resonator 2 and the tuning fork type crystal resonator 3 are mounted, the semiconductor element 8 and the AT cut type crystal resonator are included in the same piezoelectric device. 2. The tuning fork crystal unit 3 and peripheral electronic parts 4 can be arranged with high density along with the wiring conductor 6 and the wiring path can be shortened, so that power consumption during standby is extremely small. If it uses, the thing excellent in the usability which can be used without charging over a long term can be provided. In addition, it is possible to effectively reduce the size and power consumption of electronic devices such as mobile phones in which such piezoelectric devices are used as components.

In addition, as described above, the lid 7 is formed of a material formed by containing and dispersing a porous powder and a metal powder made of porous ceramics, sol-gel glass or silica gel in a resin, so that the semiconductor element 8 can be operated. Since electromagnetic waves due to the flowing high-frequency current are effectively prevented from leaking to the AT-cut crystal resonator 2 and the tuning-fork crystal resonator 3 side, the AT-cut crystal resonator 2 and the tuning-fork crystal resonator 3 It is possible to prevent the oscillation from becoming unstable due to mutual interference in the recess 5 of the insulating base 1 to be accommodated.

  In the piezoelectric vibrator housing package and the piezoelectric device according to the present invention, the piezoelectric vibrators 2 and 3 and the electronic component 4 are arranged such that the electronic parts are housed in the concave part 5 located at the center of the three concave parts 5 and the both ends. By placing the piezoelectric vibrators 2 and 3 in the recesses 5 positioned at the center, the AT cut type crystal vibrator 2 that generates vibration with a small amplitude and the tuning fork type crystal vibrator 3 that generates vibration with a large amplitude are provided on the outermost side. It is possible to suppress interference between the AT-cut crystal resonator 2 and the tuning-fork crystal resonator 3 by the concave portion 5 that is disposed in the center and located in the center.

  Further, in the present invention, as shown in the plan layout view of the piezoelectric vibrators 2 and 3 in FIG. 2B, the piezoelectric vibrators 2 and 3 are formed of a rectangular AT-cut crystal vibrator 2 and a rectangular tuning fork. The quartz crystal resonator 3 is preferably housed separately in the recesses 5 located at both ends so that the long side directions thereof are parallel to each other. The piezoelectric vibrators 2 and 3 are separately accommodated in the concave portions 5 positioned at both ends so that the long side directions are parallel to each other, so that the piezoelectric vibrators 2 and 3 are formed in the three concave portions 5 formed on the upper surface of the insulating substrate 1. 3 and the electronic component 4 can be effectively accommodated with a small mounting area.

  As described above, the piezoelectric vibrators 2 and 3 are composed of the rectangular AT-cut crystal vibrator 2 and the rectangular tuning fork crystal vibrator 3, and both ends thereof are parallel to each other so that their long sides are parallel to each other. Since the piezoelectric vibrators 2 and 3 can be vacuum-sealed in the separate concave parts 5 at the same time, the piezoelectric vibrators 2 and 3 can stably oscillate for a long period of time. Is possible.

  Here, when the piezoelectric vibrators 2 and 3 are separately accommodated in the recesses 5 at both ends so that the long side directions thereof are parallel to each other, the ends connected by the conductive adhesive or the like of the piezoelectric vibrators 2 and 3 Are arranged so as to be separated from each other (for example, as shown in FIG. 2B, an end portion to which the AT-cut type crystal resonator 2 is connected and an end portion to which the tuning fork type crystal resonator 3 is connected are respectively arranged. It is desirable to have a structure that is provided vertically and spaced apart. With such a structure, the most vibrated portion of the AT-cut crystal resonator 2 whose free end vibrates in the vertical direction, and the most vibrated portion of the tuning fork type crystal resonator 3 that vibrates in the left-right direction, Since it is possible to widen the interval, it is possible to effectively prevent a change in oscillation frequency (oscillation noise) from being caused by a resonance action, and to provide a piezoelectric device that is further excellent in oscillation frequency accuracy Can do.

  Further, as shown in the cross-sectional view of the piezoelectric device in FIG. 2A, a step is provided on the bottom surface of the concave portion 5 on the side where either the piezoelectric vibrator 2 or 3 of the concave portion 5 is accommodated, thereby Are preferably mounted so that their heights are different. Thereby, the heights of the vibration surfaces of the piezoelectric vibrators 2 and 3 can be made different from each other, and the oscillation frequency characteristics of the piezoelectric vibrators 2 and 3 are further improved by effectively suppressing mutual interference. Can be. The step on the bottom surface of the recess 5 is obtained by cutting, for example, a ceramic green sheet, which is the same as that for forming the insulating substrate 1, into a portion that will be the bottom surface of the recess 5 in the ceramic green sheet that is to be the insulating substrate 1. It can be formed by laminating.

  Furthermore, in order to effectively prevent the vibration wave of one of the piezoelectric vibrators 2 and 3 from being reflected by the inner surface of the recess 5 or the lid 7 and affecting the other piezoelectric vibrator 2 or 3, Suppressing vibration wave resonance by forming irregularities on the inner surface and the upper surface of the lid body 7, or by applying a low elastic modulus material or a porous body on the inner surface of the concave portion 5 and the lower surface of the lid body 7. May be. Examples of such a low elastic modulus material include a resin material containing a rubber component, and examples of the porous body include porous glass such as porous ceramics and sol-gel glass, and resin containing porous powder such as silica gel. Materials and the like.

  Similarly, in order to suppress vibration wave resonance, a cavity is formed inside the lid body 7, and a gel-like substance such as polymer gel or grease is filled in the cavity so as to absorb the vibration wave. Also good. Furthermore, particles such as spherical ceramics and spherical resins may be dispersed in this gel substance. Thereby, a vibration wave can be absorbed more effectively.

  Further, in order to prevent electromagnetic waves from the semiconductor element 8 from affecting the piezoelectric vibrators 2 and 3, irregularities are formed on the main surface of the lid 7 and the inner surface of the frame portion 10, or a metallized layer, a plating layer, A metal layer 11 such as a thin film metal layer or a conductive resin layer may be formed and shielded. For the same purpose, a shield layer 12 such as a metal layer may be formed immediately below the recess 5 in the insulating substrate 1.

Further, in order to prevent reflection of vibration waves of the piezoelectric vibrators 2 and 3 and to prevent the electromagnetic waves from the semiconductor element 8 from affecting the piezoelectric vibrators 2 and 3, the lid body 7 is made of porous ceramics or sol-gel glass. Or it forms with resin containing the porous powder which consists of silica gel, and a metal powder . Thereby, the vibration wave and the electromagnetic wave can be effectively absorbed by the lid body 7.

  In order to further reduce the electromagnetic influence between the piezoelectric vibrators 2 and 3 and the electronic component 4, a wall between the concave portion 5 that houses the piezoelectric vibrators 2 and 3 and the concave portion 5 that houses the electronic component 4. The part may have a double structure.

  It should be noted that the present invention is not limited to the above embodiments, and various modifications may be made without departing from the gist of the present invention. For example, FIG. 1 shows an example in which the connection between the electrode of the semiconductor element 8 and the wiring conductor 6 is made by a bonding wire, but it goes without saying that it may be a flip chip connection through a solder bump or the like.

(A) is sectional drawing which shows an example of embodiment of the piezoelectric vibrator storage package and piezoelectric device of this invention, (b) is a top view of the piezoelectric vibrator storage package and piezoelectric device of (a). (A) is sectional drawing which shows the other example of embodiment of the piezoelectric vibrator accommodation package and piezoelectric device of this invention, (b) is a top view of the piezoelectric vibrator accommodation package and piezoelectric device of (a). is there. (A) is a plan view of a conventional piezoelectric vibrator housing package and piezoelectric device, and (b) is a cross-sectional view of the piezoelectric vibrator housing package and piezoelectric device of (a).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Insulation base | substrate 2 ... Piezoelectric vibrator (AT cut type crystal vibrator)
3 ... Piezoelectric vibrator (tuning fork type crystal vibrator)
4 ... Electronic components 5 ... Recess 6 ... Wiring conductor 7 ... Cover body 8 ... Semiconductor element 10 ... Frame

Claims (4)

An insulating base having three recesses formed on the upper surface, a frame formed around the three recesses on the upper surface of the insulating base, and an inner surface of the frame to the outer surface of the insulating base. A wiring conductor, a lid formed of a resin containing porous powder and metal powder made of porous ceramics, sol-gel glass or silica gel, and attached to the upper surface of the insulating base so as to close the three recesses; One of the three concave portions is accommodated in one of the AT-cut type crystal resonator and the tuning-fork type crystal resonator which is a piezoelectric vibrator, and the other one is accommodated in the other, A package for accommodating a piezoelectric vibrator, wherein an electronic component is housed in another one and a semiconductor element is mounted on the upper surface of the lid.   The three recesses are formed in a line, the piezoelectric vibrators are accommodated in the recesses located at both ends, and the electronic components are accommodated in the recesses located in the center. The package for storing a piezoelectric vibrator according to claim 1.   The package for accommodating a piezoelectric vibrator according to claim 1, wherein a step for mounting the piezoelectric vibrator is provided on a bottom surface of a concave portion on a side for housing either of the piezoelectric vibrators.   The piezoelectric vibrator housing package according to any one of claims 1 to 3, the piezoelectric vibrator housed in the recess and having an electrode electrically connected to the wiring conductor, and the recess And the electronic component having an electrode electrically connected to the wiring conductor and the semiconductor element mounted on the upper surface of the lid and having the electrode electrically connected to the wiring conductor. A piezoelectric device characterized by that.

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