JP2006041927A - Package for housing piezoelectric resonator, and piezoelectric device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a package for housing a piezoelectric resonator which can be miniaturized, can delicately adjust an oscillation frequency, is excellent in characteristics such as oscillation frequency characteristics of the piezoelectric resonator, and is excellent in the reliability of electric connection to an external electric circuit etc., and to provide a piezoelectric device. <P>SOLUTION: The package for housing a piezoelectric resonator is provided with an insulating base 1 having a first recess 5 formed on its top surface, and a second recess 12 formed on its bottom surface; a frame 10 formed around the entire periphery of the first recess 5 of the top surface of the insulating base 1; a wiring conductor 6 formed from the inside of the frame toward the external surface of the insulating base 1; and a lid 7 attached on the top surface of the insulating base 1 so as to close the first recess 5. Piezoelectric resonators 2, 3 and a first electronic component 4 are housed in the first recess 5, a semiconductor element 8 is mounted on the top surface of the lid 7, and a second electronic component 11 for adjusting frequencies of the piezoelectric resonators 2, 3 is housed in a second recess 12. <P>COPYRIGHT: (C)2006,JPO&NCIPI

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 a single package as a piezoelectric resonator, and the package is used for controlling a semiconductor element 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. In addition, when the main power supply of the electronic device is turned off, the tuning fork type crystal resonator for the sub clock (for standby operation) 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.

In general, adjustment of the oscillation frequency oscillated by the piezoelectric vibrators 52 and 53 of the piezoelectric device is performed by changing the capacitance of the capacitive element, which is the reactance of the oscillation circuit, and changing the oscillation frequency of the oscillation circuit. ing. As a typical method for finely adjusting the oscillation frequency by changing the capacitance of the capacitive element, the capacitance is changed by directly changing the variable capacitive element provided on the oscillation circuit. Is.
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 as described above, the 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, the piezoelectric vibrators 53 and 54 are accommodated in the recess 55, and an electronic component 59 such as a capacitive element for adjusting the oscillation frequency to be obtained is mounted, and then the lid 62 is bonded to the sealing metallized layer 58. If the semiconductor element 52 is mounted on the substrate 1, the electrical characteristics such as the capacitance of the electronic component 59 change due to heat applied by heat treatment during lid bonding or semiconductor element mounting bonding. Therefore, there is a problem in that the predetermined oscillation frequency cannot be obtained.

  Further, usually, the piezoelectric vibrators 53 and 54 are sealed in the recess 55 by a lid 62, and the semiconductor element 52 and the electronic component 59 are sealed so as to cover the upper surface with a resin (not shown). Yes. Covering the substrate 51 with this resin also shifts the oscillation frequency to be obtained by changing the electrical characteristics such as the electrostatic capacity of the electronic component 59 between the wiring conductors formed on the substrate 51, and the predetermined oscillation. There was a problem that the frequency could not be obtained.

  Further, when the semiconductor element 52, the AT-cut type crystal unit 53, the piezoelectric unit such as the tuning fork type crystal unit 54, and the electronic component 59 are simultaneously mounted and accommodated on the substrate 51, the electric circuit is generated. There has been a problem that electromagnetic waves have an adverse effect on the oscillation frequency characteristics of the piezoelectric vibrators 53 and 54.

  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 frequently used ceramics (alumina ceramics, etc.), the input / output terminal 60 disposed on the lower surface of the outer peripheral portion of the substrate 51 and the main surface of the external circuit substrate 61 by the temperature cycle after connection. There is a problem that a thermal stress is generated between the connection pad and the connection pad formed on the, and a defect such as a solder crack or disconnection occurs in the connection portion of the input / output terminal 60 due to the thermal stress.

  The present invention has been devised in view of the problems of the prior art, and its purpose is to reduce the size even if the piezoelectric vibrator is housed together with other electronic components such as a semiconductor element. In order to obtain a predetermined oscillation frequency of the circuit, it is possible to finely adjust the oscillation frequency, and the piezoelectric vibrator has excellent characteristics such as oscillation frequency characteristics over a long period of time. An object of the present invention is to provide a piezoelectric vibrator housing package and a piezoelectric device that are excellent in reliability.

  The package for accommodating a piezoelectric vibrator of the present invention includes an insulating base having a first recess formed on the upper surface and a second recess formed on the lower surface, and around the first recess on the upper surface of the insulating base. A frame formed over the entire circumference, a wiring conductor formed from the inside of the frame to the outer surface of the insulating base, and a lid attached so as to close the first recess on the upper surface of the insulating base A piezoelectric vibrator and a first electronic component are housed in the first recess, a semiconductor element is mounted on the upper surface of the lid, and the piezoelectric vibrator is placed in the second recess. A second electronic component for adjusting the frequency is accommodated.

  In the piezoelectric vibrator housing package of the present invention, it is preferable that the piezoelectric vibrator includes an AT-cut crystal vibrator and a tuning fork crystal vibrator.

  In the piezoelectric vibrator housing package according to the present invention, preferably, the piezoelectric vibrator includes an elongated AT-cut type quartz vibrator and an elongated tuning fork type quartz vibrator, and the longitudinal directions thereof are orthogonal to each other. It is housed in the first 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 first recess and having an electrode electrically connected to the wiring conductor, and the first The first electronic component housed in one recess and the electrode is electrically connected to the wiring conductor, and mounted on the upper surface of the lid, and the electrode is electrically connected to the wiring conductor The semiconductor device includes a second electronic component for adjusting the frequency of the piezoelectric vibrator housed in the second recess.

  According to the package for housing a piezoelectric vibrator of the present invention, an insulating substrate having a first recess formed on the upper surface and a second recess formed on the lower surface, and around the first recess on the upper surface of the insulating substrate. A frame portion formed over the entire circumference, a wiring conductor formed from the inside of the frame portion to the outer surface of the insulating base, and a lid attached to the upper surface of the insulating base so as to close the first recess. Since the piezoelectric vibrator and the first electronic component are accommodated in the first recess and the semiconductor element is mounted on the upper surface of the lid, for example, it is the minimum necessary for mounting the semiconductor element. In the plane area of the insulating substrate, not only the semiconductor element but also the piezoelectric vibrator and the first and second electronic components can be arranged vertically and accommodated, and the piezoelectric vibrator housing package can be downsized.

  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 the first electronic component and the space in which the semiconductor element is mounted can be effectively electromagnetically blocked by the lid, and the electromagnetic wave generated by the semiconductor element or the like can be The adverse effect on the child 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.

  Also, since the second electronic component for adjusting the frequency of the piezoelectric vibrator is accommodated in the second concave portion, the piezoelectric vibrator and the first electronic component are accommodated in the concave portion. After heat treatment to attach the lid so as to block, after mounting the semiconductor element on the lid and sealing with resin, finally by the second electronic component (capacitance element or inductor element), Since the oscillation frequency to be obtained can be adjusted, the second electronic component is affected by the heat treatment when mounting the lid or mounting the semiconductor element, or by the resin sealing the semiconductor element. There is nothing that can be done and the oscillation frequency can be finely adjusted.

  Also, depending on the type of the second electronic component (capacitance element or inductor element) for adjusting the frequency to be mounted last, various frequencies can be adjusted. In the same type of piezoelectric device, oscillation of various types of frequencies is possible. Therefore, it is possible to provide a dual clock module type piezoelectric device.

  In the piezoelectric vibrator housing package of the present invention, it is preferable that the piezoelectric vibrator is composed of an AT cut type crystal vibrator and a tuning fork type crystal vibrator, so that a so-called dual clock module type piezoelectric device can be made compact. Therefore, it is possible to effectively reduce the size of an electronic device such as a mobile phone in which such a piezoelectric device is used as a component. 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.

  In the piezoelectric vibrator housing package of the present invention, it is preferable that the piezoelectric vibrator is composed of an elongated AT-cut crystal resonator and an elongated tuning fork crystal resonator, and the longitudinal directions thereof are orthogonal to each other. Since it is housed in the first recess, the largest vibration part of the AT-cut type crystal vibrator whose free end vibrates in the vertical direction and the largest vibration part of the tuning fork type crystal vibrator that vibrates in the horizontal direction. By widening the interval between them and shifting the direction of vibration, it is possible to effectively prevent a change in oscillation frequency (oscillation noise) from occurring due to the resonance action, and to achieve a piezoelectric device with even better oscillation frequency accuracy. Can be provided.

  According to the piezoelectric device of the present invention, the piezoelectric vibrator housing package having the above configuration, the piezoelectric vibrator housed in the first recess and the electrode electrically connected to the wiring conductor, and the first A first electronic component that is housed in the recess of the electrode and the electrode is electrically connected to the wiring conductor; a semiconductor element that is mounted on the upper surface of the lid and the electrode is electrically connected to the wiring conductor; Since the second electronic component for adjusting the frequency of the piezoelectric vibrator housed in the second recess is provided, the size can be reduced, and the piezoelectric vibrator has an oscillation frequency over a long period of time. In addition to excellent characteristics such as characteristics, the reliability of electrical connection to an external electric circuit or the like can be excellent.

  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 in a state without a lid and a semiconductor element, and FIG. It is sectional drawing in the -A 'line.

  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, and 4 is a first electronic component. 5 is a first recess, 10 is a frame, 6 is a wiring conductor formed from the inside of the frame to the outer surface of the insulating substrate 1, 7 is a lid, 8 is a semiconductor element, and 11 is a second electronic component. , 12 are second recesses.

  The insulating base 1, the wiring conductor 6, the frame portion 10, and the lid body 7 mainly constitute a piezoelectric element storage package of the present invention, and the piezoelectric vibrator is placed in the first recess 5 formed on the upper surface of the insulating base 1. The AT-cut crystal resonator 2, the tuning-fork crystal resonator 3, and the first electronic component 4 are accommodated, and a lid 7 is attached so as to close the first recess 5 on the upper surface of the insulating base 1. As a result, the AT-cut crystal resonator 2, the tuning fork crystal resonator 3, and the first electronic component 4 are placed inside each container formed by the first recess 5 and the lid 7 of the insulating base 1. It is stored airtight. Then, the semiconductor element 8 is mounted on the upper surface of the lid body 7, and the second electronic component 11 for adjusting the frequency of the piezoelectric vibrators 2 and 3 is accommodated in the second recess 12. A piezoelectric device is basically constructed. 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 insulating substrate 1 has a first concave portion 5 for accommodating the piezoelectric vibrators 2 and 3 on the upper surface, and the first 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 the first electronic component 4 can be hermetically sealed.

  The insulating base 1 has a second recess 12 formed on the lower surface, and a second electronic component 11 (capacitive element) for adjusting the frequency of the wiring conductor formed at the bottom of the second recess 12. And the inductor element), the oscillation frequency to be obtained can be adjusted, such as capacitance adjustment including fluctuations occurring at the time of assembly, and the frequency can be adjusted even after the assembly of the piezoelectric device is completed.

  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. Thereafter, the ceramic green sheet is appropriately punched to form a square plate and a plurality of square punched portions formed in the center, and the square plate is located in the middle layer. In addition, a laminate having a first recess 5 on the upper surface and a second recess 12 on the lower surface is formed by stacking up and down so that the one having the rectangular punched portion is positioned in the upper layer and the lower layer, The laminate is produced by firing at a high temperature (about 1600 ° C.).

  A lid 7 is attached to the upper surface of the insulating base 1 so as to close the first recess 5. The lid body 7 functions to seal the piezoelectric vibrators 2 and 3 and the first electronic component 4 by closing the first 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.

  The lid body 7 is formed of a metal such as an iron-nickel-cobalt alloy or an iron-nickel alloy, a ceramic material such as an aluminum oxide sintered body or glass ceramic, an organic resin containing metal powder, or the like. For example, if the lid 7 is made of an iron-nickel-cobalt alloy, the lid 7 is formed by subjecting a plate material of the iron-nickel-cobalt alloy to predetermined metal processing such as cutting or etching.

  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. . In particular, when the metal lid 7 is bonded and fixed with an adhesive having excellent conductivity and heat conductivity such as solder and silver paste, the heat generated in the semiconductor element 8 can be dissipated well, and the semiconductor element 8 It is possible to effectively prevent malfunction due to temperature rise.

  A frame portion 10 is formed on the upper surface of the insulating base 1 so as to surround the entire first recess 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 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 body 7, the piezoelectric vibrators 2 and 3 and the first electronic component 4 housed in the first recess 5, These function as conductive paths for leading them to the outer surface of the insulating substrate 1 and electrically connecting them to an 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 first electronic component 4 are accommodated in the first recess 5 of the insulating base 1, and each electrode is connected to the wiring conductor 6 with a conductive connection material such as solder or bonding wire (see FIG. The semiconductor element 8 is mounted on the upper surface of the lid body 7 after the recess 5 is closed with the lid body 7, and the electrode of the semiconductor element 8 is bonded to the exposed portion of the wiring conductor 6. And the like, and the semiconductor element 8 is sealed with a sealing resin 9 if necessary, and then a second for adjusting the frequency of the piezoelectric vibrators 2 and 3 in the second recess 12. A piezoelectric device is manufactured by housing the electronic component 11 (capacitance element or inductor element). In this case, an oscillation circuit is formed between the piezoelectric vibrators 2 and 3, the first electronic component 4, the semiconductor element 8, the second electronic component 11, and the like.

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

  With the above configuration, in the piezoelectric vibrator housing package and the piezoelectric device of the present invention, the insulating base 1 in which the first concave portion 5 is formed on the upper surface and the second concave portion 12 is formed on the lower surface, and the insulating base A frame portion 10 formed over the entire circumference of the first recess 5 on the upper surface of 1, a wiring conductor 6 formed from the inside of the frame portion 10 to the outer surface of the insulating base 1, and an upper surface of the insulating base 1. A lid 7 attached so as to close the first recess 5, and the piezoelectric vibrators 2 and 3 and the first electronic component 4 are accommodated in the first recess 5. Since the semiconductor element 8 is mounted on the upper surface and the second electronic component 11 for adjusting the frequency of the piezoelectric vibrators 2 and 3 is accommodated in the second recess 12, for example, for mounting the semiconductor element 8 Not only the semiconductor element 8 but also the plane area of the insulating base 1 that is the minimum necessary. Electric vibrator 2 and 3, the first and second electronic components 4 and 11 can also be accommodated, it is possible to reduce the size of the package piezoelectric vibrator housing.

  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 first electronic component 4 and the space in which the semiconductor element 8 is mounted can be effectively electromagnetically blocked by the lid body 7. The electromagnetic wave generated by the first electronic component 4 or the like is effectively prevented from adversely affecting the piezoelectric vibrators 2 and 3, and the characteristics of the piezoelectric vibrators 2 and 3 (for example, AT cut type crystal vibrator and tuning fork type crystal vibration) The oscillation frequency characteristics of a piezoelectric vibrator such as a child can be maintained satisfactorily. In addition, when improving such electromagnetic interruption | blocking more, the lid | cover body 7 is based on the difference in a linear expansion coefficient with the insulation base | substrate 1 at the time of a temperature cycle, in order to make the above-mentioned electromagnetic interruption | blocking effective. In consideration of thermal stress, metal material such as iron-nickel-cobalt alloy or iron-nickel alloy, or a material in which a metallized layer is formed on the entire surface of a ceramic plate, or formed by dispersing metal powder in resin It is preferable to form with a material.

  The piezoelectric vibrator is, for example, the AT-cut type crystal vibrator 2 or the tuning fork type crystal vibrator 3 as described above, and oscillates at a predetermined frequency to oscillate a reference signal such as a frequency for time or communication. Function. 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 first electronic component 4 is, for example, a surface-mounted passive element such as a capacitive element (a well-known ceramic capacitor or the like) or an inductor element, and the second electronic component accommodated in the second recess 12. 11 and the piezoelectric vibrators 2 and 3 and the semiconductor element 8 form an oscillation circuit. The mounting of the first electronic component 4 in the first recess 5 and the mounting of the second electronic component 11 in the second recess 12 are performed by, for example, soldering an electrode to an exposed portion of the wiring conductor 6. This is done by connecting them electrically and mechanically.

  As the second electronic component 11, for example, a capacitive element such as a rotary trimmer capacitor or a chip capacitor is used, and the capacitive element can be statically operated by directly operating the trimmer capacitor or pattern trimming the chip capacitor. The frequency is adjusted by changing the capacitance.

  Accordingly, various frequencies can be adjusted according to the type of the second electronic component 11 and the change in capacitance, etc., and a dual type capable of oscillating various types of frequencies in the same type of piezoelectric device. A clock module type piezoelectric device can be provided.

  In this case, the second electronic component 11 is housed in the second recess 12 on the lower surface side opposite to the upper surface side on which the piezoelectric vibrators 2 and 3 and the semiconductor element 8 are housed and mounted. Separately from 2, 3 and the semiconductor element 8, the piezoelectric device can be appropriately selected, accommodated, and mounted according to the application, required characteristics, and the like of the piezoelectric device. Therefore, it is easy to manufacture and supply the piezoelectric device according to the application.

  Even when the second electronic component 11 is housed in the second recess 12 after the semiconductor element 8 is mounted, an insulating base is provided between the semiconductor element 8 and the portion where the second electronic component 11 is mounted. 1, the lid body 7, etc., even if heat is applied when the second electronic component 11 is joined to the bottom surface of the second recess 12, the heat is blocked to some extent from being transmitted to the semiconductor element 8. Therefore, the semiconductor element 8 is not greatly affected by heat, and the deterioration of the characteristics of the semiconductor element 8 can be effectively prevented.

  Note that the second recess 12 only needs to secure a plane area and depth sufficient to accommodate at least the second electronic component 11, and may have a plane area smaller than that of the first recess 5. However, in order to prevent deformation of the insulating substrate 1 such as warping by matching shrinkage during firing of the insulating substrate 1 on the upper surface side and the lower surface side, the planar shape that overlaps the first recess 5 in plan view The dimensions are preferred.

  In the piezoelectric vibrator housing package and the piezoelectric device according to the present invention, the piezoelectric vibrator is preferably composed of an AT-cut crystal vibrator 2 and a tuning fork crystal vibrator 3. In this case, an oscillation circuit is formed between the AT cut type crystal resonator 2, the tuning fork type crystal resonator 3, the first electronic component 4, the second electronic component 11, and the semiconductor element 8, so-called dual clock module type. The 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 type crystal resonator 3, the first electronic component 4, and the second electronic component 11 can be arranged with high density together with the wiring conductor 6, and the wiring path can be shortened. For example, when used in a mobile phone, it is possible to provide a device that is excellent in usability and can be used without being charged for a long time. 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.

  Further, as described above, the lid 7 is formed of a metal material, a material in which a metallized layer is formed on the entire surface of a ceramic plate, or a material formed by containing and dispersing metal powder in a resin, thereby forming a semiconductor element. 8 is effectively prevented from leaking to the AT-cut crystal resonator 2 and the tuning-fork crystal resonator 3 side due to the high-frequency current that flows during operation of the AT 8, so the AT-cut crystal resonator 2 and the tuning-fork crystal It is possible to prevent oscillation from becoming unstable due to mutual interference in the first recess 5 of the insulating base 1 in which the vibrator 3 is accommodated.

  In the piezoelectric vibrator housing package and the piezoelectric device of the present invention, the arrangement of the piezoelectric vibrators 2 and 3 and the first electronic component 4 is not particularly limited, but one of the piezoelectric vibrators 2 and 3 is In the case of the tuning-fork type crystal resonator 3, it is preferable to arrange the tuning-fork type crystal resonator 3 that generates vibration with a large amplitude in the outermost part to suppress interference with other parts.

  Further, in the present invention, as shown in FIG. 1A, the piezoelectric vibrators 2 and 3 are composed of an elongated AT-cut type crystal oscillator 2 and an elongated tuning fork type crystal oscillator 3, and these longitudinal directions are mutually connected. It is preferable to be accommodated together in the first recess 5 so as to be parallel.

  As described above, the piezoelectric vibrators 2 and 3 are composed of the long and narrow AT-cut type crystal vibrator 2 and the long and thin tuning fork type crystal vibrator 3, and the longitudinal directions thereof are parallel to each other in the first recess 5. Since they are housed together, the piezoelectric vibrators 2 and 3 can be simultaneously vacuum-sealed, and the piezoelectric vibrators 2 and 3 can be stably oscillated over a long period of time.

  2A and 2B, the AT-cut crystal resonator 2, the tuning-fork crystal resonator 3, and the electronic component 4 accommodated in the recess 5 have a sufficient area. , 3 in order to more effectively prevent mutual interference due to vibration between the components, the tuning-fork type crystal resonator 3 and the AT-cut type crystal resonator 2 are separated from each other by a portion having the largest vibration. It is preferable that the free ends (end portions not fixed by the conductive bonding material) are arranged so as to be separated from each other.

  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.

  In the present invention, when there is room in the space of the first concave portion 5 for accommodating the piezoelectric vibrators 2 and 3, the piezoelectric vibrators 2 and 3 are rectangular as shown in FIG. And the like, and the elongated tuning-fork type quartz crystal resonator 3 having a rectangular shape or the like, and the longitudinal directions of the crystal resonators 2 may be accommodated together in the first concave portion 5 so as to be orthogonal to each other. preferable.

  As described above, the piezoelectric vibrator is composed of the long and narrow AT-cut type crystal vibrator 2 and the long and thin tuning fork type crystal vibrator 3, and is housed together in the first recess 5 so that the longitudinal directions thereof are orthogonal to each other. Therefore, the distance between the most vibrated portion of the AT-cut type 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 is set as follows. By widening and shifting the vibration direction of these piezoelectric vibrators 2 and 3, it is possible to effectively prevent a change in oscillation frequency (oscillation noise) from occurring due to the resonance action, and to further improve the accuracy of the oscillation frequency. It is possible to provide an excellent piezoelectric device.

  In addition, it is preferable that a step is provided on the bottom surface of the first recess 5 that accommodates the piezoelectric vibrators 2 and 3, and the piezoelectric vibrators 2 and 3 are mounted so as to have different heights. 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. As for the step of the bottom surface of the first recess 5, for example, a ceramic green sheet similar to that for forming the insulating substrate 1 is predetermined in a portion of the ceramic green sheet that becomes the insulating substrate 1 that is the bottom surface of the first recess 5. It can be formed by laminating those cut to dimensions.

  Further, in order to effectively prevent resonance of the vibration wave due to the difference in vibration frequency between the piezoelectric vibrators 2 and 3, the piezoelectric vibrators are provided on the bottom surface of the first recess 5 and the bottom surface of the lid body 7. A protrusion may be formed so as to partition between two and three.

  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 and the lid 7 and affecting the other piezoelectric vibrators 2 and 3, By forming irregularities on the inner surface of the concave portion 5 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 first concave portion 5 and the lower surface of the lid body 7, The occurrence of resonance may be suppressed. 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 upper surface of the lid 7 and the inner surface of the frame portion 10, or metallized layers, plated layers, thin films A metal layer such as a metal layer or a conductive resin layer may be formed and shielded.

  Further, in order to prevent reflection of vibration waves of the piezoelectric vibrators 2 and 3 and to prevent electromagnetic waves from the semiconductor element 8 from affecting the piezoelectric vibrators 2 and 3, the lid 7 is made of metal powder and porous powder. It may be formed of a resin that contains the resin, whereby the lid body 7 can effectively absorb vibration waves and electromagnetic waves.

  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 a plan view showing a piezoelectric vibrator housing package and a piezoelectric device according to an embodiment of the present invention without a lid and a semiconductor element, and (b) is a piezoelectric vibrator housing of (a). It is sectional drawing in the AA 'line | wire of the package for packages and a piezoelectric device. (A)-(c) is an enlarged plan view which shows the various examples of the arrangement | positioning form of the piezoelectric vibrator in the package for piezoelectric vibrator accommodation of this invention, and a piezoelectric device. (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

1 ... Insulating substrate 2 ... Piezoelectric vibrator (AT-cut crystal vibrator)
3 ... Piezoelectric vibrator (tuning fork type crystal vibrator)
4... First electronic component 5... First recess 6... Wiring conductor 7. Frame part 11 ... second electronic component 12 ... second recess

Claims (4)

An insulating substrate having a first recess formed on the upper surface and a second recess formed on the lower surface; a frame portion formed around the first recess on the upper surface of the insulating substrate; and A wiring conductor formed from the inside of the frame portion to the outer surface of the insulating base, and a lid attached to the upper surface of the insulating base so as to close the first recess. A piezoelectric vibrator and a first electronic component are housed in the recess, a semiconductor element is mounted on the upper surface of the lid, and a second electronic component for adjusting the frequency of the piezoelectric vibrator in the second recess A package for accommodating a piezoelectric vibrator, wherein: 2. The piezoelectric vibrator housing package according to claim 1, wherein the piezoelectric vibrator comprises an AT cut type crystal vibrator and a tuning fork type crystal vibrator. The piezoelectric vibrator includes an elongated AT-cut type quartz vibrator and an elongated tuning fork type quartz vibrator, and is housed in the first recess so that the longitudinal directions thereof are orthogonal to each other. Item 3. A package for storing a piezoelectric vibrator according to Item 2. The piezoelectric vibrator housing package according to any one of claims 1 to 3, the piezoelectric vibrator housed in the first recess and having an electrode electrically connected to the wiring conductor, The first electronic component housed in the first recess and the electrode is electrically connected to the wiring conductor, and mounted on the upper surface of the lid, and the electrode is electrically connected to the wiring conductor A piezoelectric device comprising: the connected semiconductor element; and a second electronic component for adjusting a frequency of the piezoelectric vibrator housed in the second recess.

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