JPH0865051A - Piezoelectric oscillator - Google Patents

Abstract

PURPOSE: To make a piezoelectric oscillator for which an oscillation circuit including a piezoelectric vibrator is integrally formed small in side, small in packaging area and simple in manufacture. CONSTITUTION: This piezoelectric oscillator 10 is in a three-stage structure for which a base body 22, a frame body 11 and a sealing member 35 are successively superimposed. Then, the piezoelectric vibrator 13 is provided through supporting beams 14 on the substrate 12 for the vibrator of the frame body 11 and an inverter (COMS circuit) is laminated and formed. Also, on the integrated circuit board 23 of the base body 22, a CR circuit part composed of a resistor and a capacitor is laminated and formed. Then, by connecting the substrate 12 for the vibrator and the intergrated circuit board 23 by electrodes 27A-27D or the like, the oscillation circuit composed of the inverter, the piezoelectric vibrator 13 and the CR circuit part is formed inside the piezoelectric oscillator 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a piezoelectric thin film oscillator using a piezoelectric thin film, and a piezoelectric oscillator in which a circuit portion forming an oscillation circuit is integrated with the piezoelectric thin film oscillator. The present invention relates to a piezoelectric oscillator suitable for use as a clock pulse oscillator for machines.

[0002]

2. Description of the Related Art Generally, there is known a piezoelectric thin film vibrator having a structure in which a piezoelectric thin film made of ZnO, AlN or the like is formed on a thin plate of a constant elastic material or a silicon material. Such a piezoelectric thin film vibrator is often applied as an oscillator in the field of microelectronics and the like, and miniaturization is required.

On the other hand, high density integration of semiconductor integrated circuits is remarkable, and electronic parts such as resistors and capacitors and CMOS
A semiconductor integrated technology for forming electronic circuits on the surface and inside of a substrate by stacking integrated circuits and the like has become a general technology.

From the above technical background, an oscillator having a structure in which a piezoelectric thin film oscillator and a semiconductor integrated circuit are integrated and peripheral electronic circuits are also known is known. The integrated type piezoelectric thin film functional element disclosed in Japanese Patent Laid-Open No. 63-187713 will be briefly described with reference to FIG.

In the figure, reference numeral 1 denotes an integrated piezoelectric thin film functional element according to the prior art.
Is an integrated oscillation circuit section 3 formed on the right side of the semiconductor substrate 2, a piezoelectric thin film oscillator 4 located on the left side of the integrated oscillation circuit section 3 and formed on the semiconductor substrate 2, and the piezoelectric thin film. The oscillator 4 and the integrated oscillation circuit section 3 are generally constituted by wirings 5 and 6 for electrically connecting them.

With the integrated piezoelectric thin film functional element 1 thus constructed, the integrated oscillating circuit portion 3 and the piezoelectric thin film oscillator 4 are provided on the same semiconductor substrate 2 to be integrated with each other so as to achieve miniaturization. There is.

[0007]

By the way, in the above-mentioned prior art, the integrated oscillation circuit section 3 is formed on the single semiconductor substrate 2.
Although the piezoelectric thin film vibrator 4 and the piezoelectric thin film vibrator 4 are formed and integrated with each other to achieve miniaturization, the integrated oscillation circuit unit 3 and the piezoelectric thin film vibrator 4 are arranged side by side on the semiconductor substrate 2. Therefore, the area becomes large when viewed in plan,
There is a problem that the mounting area becomes large.

Further, in the prior art, since the integrated oscillation circuit portion 3 and the piezoelectric thin film oscillator 4 are arranged apart from each other, the wirings 5 and 6 are formed to electrically connect them. As a result, the wirings 5 and 6 increase stray capacitance and wiring resistance,
There is a problem that it causes the performance of the piezoelectric thin film vibrator 4 to deteriorate.

Further, in the prior art, since there is a concern that the wirings 5, 6 will be broken during the manufacturing process, the semiconductor substrate 2
There is a problem that the manufacturing method is complicated, such as forming an inclination at the step between the piezoelectric thin film vibrator 4 and the piezoelectric thin film vibrator 4.

The present invention has been made in view of the above-mentioned problems of the prior art, and reduces the mounting area and simplifies the electrical connection between the piezoelectric thin film vibrator and the integrated circuit to simplify the manufacturing. It is an object of the present invention to provide a piezoelectric oscillator that can be manufactured.

[0011]

In order to solve the above-mentioned problems, a piezoelectric oscillator according to a first aspect of the present invention is a piezoelectric oscillator in which a piezoelectric vibrator and a first circuit portion are provided on a first substrate made of silicon. A case portion, a second case portion provided on a second substrate with the piezoelectric vibrator and a second circuit portion to be electrically connected to the first circuit portion, and the first and second cases. In order to unify the parts, the second substrate is joined to the first substrate to form an oscillator circuit formed by the piezoelectric vibrator, the first circuit part and the second circuit part. Has been adopted.

A piezoelectric oscillator according to a second aspect of the invention is a piezoelectric oscillator on the side of the first substrate, a first circuit portion, and a second circuit portion.
In order to electrically connect the second circuit portion on the board side of
A plurality of electrodes are respectively provided on one side surface of the first substrate and the other side surface of the second substrate facing the one side surface of the first substrate.

Further, the piezoelectric oscillator according to claim 3 is
A sealing member for sealing the piezoelectric vibrator is provided on the other side surface of the first substrate.

[0014]

According to the structure of claim 1, the piezoelectric vibrator, the first
The oscillation circuit including the circuit section and the second circuit section is made into a single chip component, and the piezoelectric vibrator and the first circuit section are provided.
By superimposing and integrating the first substrate on which the circuit portion is formed and the second substrate on which the second circuit portion is formed, downsizing can be achieved, and a large mounting area can be achieved. Can be made smaller.

According to the second aspect of the present invention, the piezoelectric vibrator on the first substrate side, the first circuit portion and the second circuit portion on the second substrate side are connected by a plurality of electrodes. This eliminates the need for forming metal thin film wiring, wire bonding, etc., and facilitates manufacturing.

Further, according to the structure of claim 3, the second substrate is provided on one side of the first substrate in an overlapping manner, and the sealing member is provided on the other side of the first substrate in an overlapping manner. As a result, since the piezoelectric vibrator formed on the first substrate is sealed, the chip component can be made small.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 1 to 15. In the embodiment, a piezoelectric oscillator is mounted on a computer board to oscillate a computer clock pulse. The case where the oscillator is used as an oscillator will be described as an example.

First, a first embodiment of the present invention will be described with reference to FIGS.

In the figure, reference numeral 10 denotes a piezoelectric oscillator according to this embodiment. The piezoelectric oscillator 10 is an integrated piezoelectric oscillator and an oscillation circuit around the piezoelectric oscillator, and is suitable for use as a surface mounting component. It is a simple oscillator. That is, the piezoelectric oscillator 10 includes an oscillation circuit 34, which will be described later, as shown in FIG.
Is configured, for example, when it is desired to form an oscillation circuit for clock pulses on a computer circuit board,
It is sufficient to mount the piezoelectric oscillator 10.

Further, the piezoelectric oscillator 10 according to the present embodiment.
As shown in FIG. 2, the frame body 11 provided with the piezoelectric vibrator 13 and the like, which will be described later, is superposed and joined on the base body 22, and the sealing member 35 is superposed and joined on the frame body 11. It has a three-stage structure.

Reference numeral 11 denotes a frame body as a first case portion provided in the middle stage of the piezoelectric oscillator 10 according to the present embodiment, and 12 denotes a first substrate constituting the outer shape of the frame body. The oscillator substrate is shown. Then, the vibrator substrate 12
Is formed of a silicon material, and has a frame shape in which the center side is removed by etching. The lower surface of the vibrator substrate 12 serves as a lower bonding surface 12A that is bonded to the integrated circuit board 23, and the upper surface of the vibrator substrate 12 serves as an upper bonding surface 12B that is bonded to the sealing member 35. There is.

Reference numeral 13 is a support beam 14 and 1 on the vibrator substrate 12.
4 shows a piezoelectric vibrator (hereinafter referred to as a vibrator 13) that is vibratably supported via the diaphragm. The vibrator 13 includes a diaphragm 15 formed of a silicon material in a square thin plate, and a diaphragm 15 on the diaphragm 15. The piezoelectric thin film 16 is formed by sputtering or other means, and the pair of metal thin films 17A and 17B is formed on both upper and lower surfaces of the piezoelectric thin film 16.

The piezoelectric thin film 16 is made of ZnO, AlN.
A thin film made of a piezoelectric material such as
A and 17B are thin films made of a metal material such as Al and Au-Cr. As shown in FIG. 6, the vibrator 13 is formed by sequentially laminating a metal thin film 17A, a piezoelectric thin film 16 and a metal thin film 17B on the lower surface of the vibration plate 15. As shown in FIG. 4, one end side of each of the metal thin films 17A and 17B is connected to the piezoelectric thin film 16 as described above, and the other end side thereof is connected to the support beams 14 and 1, respectively.
4 extends to the oscillator substrate 12 side through the surface of No. 4 and is connected to oscillator-side electrodes 19A and 19B described later, respectively. Then, when an electric field is applied between the metal thin films 17A and 17B via the vibrator-side electrodes 19A and 19B, the piezoelectric thin film 16 is distorted and deformed by the piezoelectric phenomenon, whereby the vibrator 13 passes through each support beam 14. It spreads and vibrates in the horizontal direction at a predetermined resonance frequency.

Reference numeral 18 denotes an inverter as a first circuit portion laminatedly formed in the vibrator substrate 12, and the inverter 18 is a CMOS integrated circuit, and is formed on a part of the vibrator substrate 12 by a semiconductor integrated technique. It is formed by stacking.

Reference numerals 19A, 19B, 19C and 19D denote four vibrator side electrodes formed on the lower bonding surface 12A of the vibrator substrate 12, and the vibrator side electrodes 19A, 19B and 19D.
C and 19D are made of a metal material and are used for the oscillator substrate 12
It is a thin plate that slightly protrudes downward from. In addition, the transducer-side electrodes 19A and 19B are formed of metal thin films 17A and
Each of them is connected to the piezoelectric thin film 16 via 17B and, as shown in FIG.
N) and the output side (OUT), respectively.
On the other hand, the vibrator-side electrodes 19C and 19D are connected to the ground section (GND) and the power supply section (VCC) of the inverter 18, respectively. In addition, the electrodes 19A, 19B, 1 for each transducer
Each connection between 9C and 19D and the inverter 18 is made by wiring such as a metal thin film.

In this case, the vibrator 13 includes the vibrator 1
All surfaces of 3 (vibrating plate 15, piezoelectric thin film 16, metal thin film 17)
A protective film (insulating film) is formed so as to cover A, the exposed surface of the metal thin film 17B, and the like. However, a protective film is not formed on the surface of the vibrator side electrodes 19A, 19B, 19C, 19D, and is connected to integrated circuit side electrodes 27A, 27B, 27C, 27D on the integrated circuit substrate 23 side which will be described later. Because of this, the metal surface is exposed.

Reference numeral 20 denotes a lower bonding surface 12 of the vibrator substrate 12.
Reference numeral 21 denotes a first joining metal portion formed on A, and reference numeral 21 denotes a second joining metal portion formed on the upper joining surface 12B of the vibrator substrate 12, respectively.
Is formed of a metal material such as Ni over the entire circumference along the frame shape of the oscillator substrate 12, and has a thickness such that the oscillator substrate 12 slightly protrudes downward and upward, respectively. have. The first bonding metal part 20 is for bonding the vibrator substrate 12 and the integrated circuit board 23, and the second bonding metal part 21 is the vibrator substrate 12 and the sealing member. It is for joining with 35.

Reference numeral 22 denotes a base body which is provided at the lower stage of the piezoelectric oscillator 10 and serves as a second case portion, and 23 denotes an integrated circuit board which is a second board forming the outer shape of the base body 22. . The integrated circuit substrate 23 is a ceramic multilayer substrate formed in a block shape, and the outer peripheral shape thereof is the same as the outer peripheral shape of the vibrator substrate 12. The upper surface of the integrated circuit board 23 is a bonding surface 23A that is bonded to the vibrator substrate 12.

Reference numeral 24 denotes a CR circuit portion as a second circuit portion which is laminated and formed in the integrated circuit board 23. The CR circuit portion 24 has a resistor 25 and a capacitor 2 as shown in FIG.
6 and 26, each of which has a predetermined connection.

Reference numerals 27A, 27B, 27C and 27D denote four integrated circuit side electrodes formed on the joint surface 23A of the integrated circuit substrate 23, and the integrated circuit side electrodes 27A, 27B and 27 are provided.
C and 27D are thin films of metal materials such as Al and Au-Cr. 12, the integrated circuit side electrodes 27A and 27B are connected to the CR circuit portion 24 by wiring such as metal thin film, and the integrated circuit side electrodes 27C and 27D are connected to the ground terminal 31 by wiring such as metal thin film. , And power supply terminals 32, respectively.

Further, the integrated circuit side electrodes 27A, 27B,
27C and 27D are respectively positioned so as to collide with the vibrator side electrodes 19A, 19B, 19C and 19D of the vibrator substrate 12 when the vibrator substrate 12 is bonded onto the integrated circuit board 23. . Further, the solder films 28, 2 are formed on the integrated circuit side electrodes 27A, 27B, 27C, 27D.
Are formed, and the integrated circuit side electrodes 27A, 27B,
27C and 27D, and the vibrator side electrode 1 of the vibrator substrate 12
9A, 19B, 19C and 19D are connected by melting each solder film 28. As a result, the integrated circuit side electrodes 27A, 27B, 27C and 27D are electrically and physically joined to the transducer side electrodes 19A, 19B, 19C and 19D.

Reference numeral 29 denotes a third joining metal portion formed on the joining surface 23A of the integrated circuit board 23. The third joining metal portion 29 is a thin film of a metal material such as Ni. It is formed over the entire circumference in the vicinity of the outer edge of 23. Further, the solder film 30 is formed on the third bonding metal portion 29, and when the vibrator substrate 12 is bonded onto the integrated circuit board 23, the third bonding metal portion 29 and the vibrator are joined together. The solder film 3 is abutted against the first bonding metal portion 20 of the soldering substrate 12.
0 is melted and joined.

Reference numerals 31, 32 and 33 denote a ground terminal, a power supply terminal and an output terminal provided on the lower surface and each side surface of the integrated circuit board 23, respectively.
2 and the output terminal 33 are each made of a metal material and fixed to the integrated circuit board 23 with an adhesive or the like.

The earth terminal 31 is the integrated circuit board 2
3 is connected to the integrated circuit side electrode 27C, and the vibrator side electrode 19C is connected to the integrated circuit side electrode 27C, thereby connecting to the ground portion of the inverter 18. Further, the ground terminal 31 is connected to each capacitor 26 of the CR circuit section 24 as shown in FIG. The power supply terminal 32 is connected to the integrated circuit side electrode 27D, and the vibrator side electrode 19D is connected to the integrated circuit side electrode 27D, thereby connecting to the power supply section of the inverter 18. Further, the output terminal 33 is connected to the CR circuit section 24 in the integrated circuit board 23 as shown in FIG.

Here, the vibrator substrate 12 of the frame body 11
The oscillator 13, the inverter 18, and the CR circuit portion 24 formed on the integrated circuit board 23 of the base 22.
The oscillator-side electrodes 19A to 19D and the integrated-circuit-side electrodes 27A to 27D are joined together to form an oscillation circuit 34 as shown in FIG.

Reference numeral 35 denotes a sealing member formed at the upper stage of the piezoelectric oscillator 10. The sealing member 35 is a small plate material made of ceramic or the like, and its outer shape is the same as the vibrator substrate 12 described above. It is formed in almost the same square shape.

Reference numeral 36 denotes a fourth joining metal portion provided on the lower surface of the sealing member 35. The fourth joining metal portion 36 is a thin film of a metal material such as Ni, and the It is formed over the entire circumference in the vicinity of the outer edge. Further, a solder film 37 is formed on the lower surface of the fourth bonding metal portion 36, and when the sealing member 35 is bonded onto the vibrator substrate 12,
The fourth bonding metal portion 36 and the second substrate 12 for the vibrator
The metal film 21 for joining is abutted, and the solder film 37 is melted and joined.

The piezoelectric oscillator 10 according to this embodiment has the above-described structure. Next, the piezoelectric oscillator 10 will be described.
In the manufacturing process of, the method of joining the frame body 11, the base 22, and the sealing member 35 will be mainly described.

That is, the piezoelectric oscillator 10 is manufactured by the frame 1
This can be performed very easily by separately manufacturing the base body 22 and the sealing member 35 as described above, and then joining and assembling them.

First, the oscillator substrate 12 of the frame 11 is bonded onto the integrated circuit substrate 23 of the base 22. At this time, each solder film 28 on the integrated circuit side electrodes 27A, 27B, 27C, 27D is melted, and the integrated circuit side electrodes 27A, 27B, 2 are formed.
7C, 27D and transducer side electrodes 19A, 19B, 19C,
19D is joined. As a result, the oscillator 13 and the inverter 18 provided on the oscillator substrate 12 side are electrically connected to the CR circuit section 24 provided on the integrated circuit substrate 23, and the oscillator circuit 34 as shown in FIG. Will be configured.

Almost at the same time, the integrated circuit board 2
Solder film 3 formed on the third joining metal portion 29 on the third side
0 is melted and the first bonding metal part 20 and the third bonding metal part 29 on the oscillator substrate 12 side are bonded. As a result, the oscillator substrate 12 and the integrated circuit substrate 23 are accurately positioned, and the lower bonding surface 12 of the oscillator substrate 12 is positioned.
A and the joint surface 23A of the integrated circuit board 23 are hermetically joined.

Next, the sealing member 35 is bonded onto the vibrator substrate 12 of the frame 11. At this time, the solder film 37 formed on the fourth bonding metal portion 36 of the sealing member 35 is melted, and the fourth bonding metal portion 36 and the second bonding formed on the vibrator substrate 12 are melted. The metal part 21 for welding is joined. As a result, the sealing member 35 is accurately positioned on the oscillator substrate 12, and the upper bonding surface 12B of the piezoelectric substrate 12 is hermetically sealed by the sealing member 35.

As a result, the vibrator 13 is integrated into the integrated circuit board 23.
With the sealing member 35, the air is hermetically sealed from the outside air. The oscillator 13, etc. can be vacuum-sealed by assembling the frame body 11, the base 22, and the sealing member 35 in a vacuum.

The order of assembling the piezoelectric oscillator 10 is not limited to the above-described order. First, the frame 11 and the sealing member 35 are joined, and then the frame 11 and the base 22 are joined. Good.

Next, the operation of the piezoelectric oscillator 10 will be described with reference to the circuit diagram of the oscillation circuit 34 shown in FIG.

For example, when the piezoelectric oscillator 10 is mounted on a computer circuit board, the earth electrode 3 is used.
1, a power supply terminal 32 and an output terminal 33 are mounted on the circuit board for a computer so as to be connected to a ground land, a power supply land, and a clock pulse land, respectively, and a predetermined DC voltage ( For example, 5 V) is supplied. As a result, the power supply voltage is supplied to the inverter 18, and the metal thin films 17A and 17A of the vibrator 13 are supplied.
An electric field due to disturbance noise or the like generated in the oscillation circuit 34 is applied between B, and the vibrator 13 mechanically vibrates at a predetermined resonance frequency. Then, this vibration is amplified to a predetermined voltage (for example, 5V) by the inverter 18, and is output from the output terminal 33 as a clock pulse.

As described above, the oscillation circuit 34 itself is generally known as a so-called Colpitts circuit, but the piezoelectric oscillator 10 according to the present embodiment has a single oscillation circuit 34 including the vibrator 13. This is integrally formed as a surface mount component, and by doing this, it is not necessary to separately form an oscillation circuit by only surface mounting the single piezoelectric oscillator 10 on the computer circuit board.

Further, in this embodiment, the piezoelectric oscillator 10 is used.
Integrated circuit board 23, vibrator substrate 12, sealing member 35
With the structure in which the piezoelectric oscillators 10 are superposed in order from the bottom, the mounting area of the piezoelectric oscillator 10 can be limited to the area of the lower surface of the integrated circuit board 23, and the mounting area can be made extremely small.

Thus, according to this embodiment having the above-described structure, the piezoelectric oscillator 10 is provided with the base 22, the frame 1
1, a sealing member 35 is superposed and joined to form a three-stage structure, the oscillator 13 and the inverter 18 are provided on the oscillator substrate 12 of the frame 11, and the CR circuit portion 24 is provided on the integrated circuit substrate 23 of the base 22. By providing it, it is possible to form a single surface-mounting component that incorporates the oscillation circuit 34 including the vibrator 13, and the piezoelectric oscillator 10 can be made extremely small.

That is, since the integrated circuit board 23 having the CR circuit section 24, the vibrator 13, the vibrator substrate 12 having the inverter 18, and the sealing member 35 are vertically stacked, the mounting area is significantly reduced. be able to.
In particular, stacking relatively large electronic components such as the capacitors 26 on the integrated circuit board 23 is an important factor for downsizing.

Further, in the manufacture of the piezoelectric oscillator 10 according to this embodiment, when the vibrator substrate 12 and the integrated circuit substrate 23 are joined, the joining metal portions 20 and 29 may be welded by the solder film 30. Well, the oscillator substrate 12
Even when the sealing member 35 is bonded on the upper side, the metal part 2 for bonding is also used.
Since the solder film 37 may be welded between the terminals 1 and 36,
The joining work at each place is very simple, and at the time of joining, the oscillator substrate 12, the integrated circuit board 23, and the sealing member 35 can be easily positioned by the surface tension (self-alignment effect) of the solder films 30 and 37. Is.

Further, when forming the oscillation circuit 34,
The vibrator 13 and the inverter 18 provided on the vibrator substrate 12 side and the CR circuit portion 24 provided on the integrated circuit board 23 side are electrically connected to the vibrator side electrodes 19A and 19A.
B, 19C, 19D and integrated circuit side electrodes 27A, 27
Since B, 27C, and 27D are welded by the solder films 28, there is no need for wire bonding or the like, and the connection work can be made very easy. Further, by directly connecting the electrodes without using wire bonding, metal thin film wiring, etc., wiring resistance, stray capacitance, etc. can be significantly reduced, and deterioration of resonance vibration of the vibrator 13 can be prevented. be able to.

Furthermore, according to this embodiment, the frame 11
By providing the sealing member 35 on the top, the vibrator 13 and the like can be hermetically sealed by the base 22 and the sealing member 35. This eliminates the need to separately provide a sealing accommodating cover or the like and accommodate the piezoelectric oscillator in the accommodating cover or the like. As a result, the size of the piezoelectric oscillator can be greatly reduced.

Next, a second embodiment of the present invention will be described with reference to FIGS. 13 to 15. The feature of this embodiment is that the vibrator substrate as the first substrate is closed on the other side. The shape of the piezoelectric oscillator is abolished from the sealing member described in the first embodiment, and the piezoelectric oscillator has a two-stage structure. In this embodiment, the same components as those of the first embodiment shown in FIGS. 1 to 12 are designated by the same reference numerals and the description thereof will be omitted.

In the figure, reference numeral 41 denotes a piezoelectric oscillator according to the present embodiment. The piezoelectric oscillator 41 is similar to the piezoelectric oscillator 10 described in the first embodiment. An oscillator that is integrated with an oscillation circuit and is suitable for use as a surface mounting component. However, the piezoelectric oscillator 41 includes a lid 42 having a vibrator 44 described later.
The piezoelectric oscillator 10 is different from the piezoelectric oscillator 10 according to the first embodiment in that it has a two-stage structure in which the above is bonded and superposed on the substrate 22 used in the first embodiment.

Reference numeral 42 denotes a lid as a first case provided at the upper stage of the piezoelectric oscillator 41, and 43 for a vibrator as a first substrate constituting the outer shape of the lid 42. The board is shown. A concave portion 43A having a concave shape is formed in the center of the oscillator substrate 43 from the lower surface toward the upper side by etching. In addition, the oscillator substrate 4
The lower surface of 3 serves as a bonding surface 43B for bonding with the integrated circuit board 23.

Reference numeral 44 denotes a piezoelectric vibrator (hereinafter referred to as “vibrator 44”) provided inside the recess 43A of the vibrator substrate 43 so as to be capable of vibrating via the support beams 45, 45. The structure is almost the same as that of the vibrator 13 according to the first embodiment shown in FIG. That is, the vibrator 44 of the present embodiment
Is a diaphragm 46 made of a silicon material, and the diaphragm 46
Piezoelectric thin film 4 formed on the surface by means such as sputtering
7 and a pair of metal thin films 48A, 48B formed on both upper and lower side surfaces of the piezoelectric thin film 47. The metal thin films 48A and 48B are omitted in FIG.

Reference numeral 49 designates an inverter as a first circuit portion laminatedly formed in the vibrator substrate 43, and the inverter 49 is the same as the inverter 18 described in the first embodiment.

Reference numerals 50A, 50B, 50C, and 50D denote four vibrator-side electrodes formed on the lower surface of the vibrator substrate 43, and the vibrator-side electrodes 50A, 50B, 50C, and 50D.
Is the vibrator-side electrode 19A, 1 described in the first embodiment.
9B, 19C and 19D are formed in substantially the same manner. In addition, the transducer-side electrodes 50A and 50B are the metal thin films 48A and 4B.
It is connected to the piezoelectric thin film 47 via 8B, and is also connected to the input side and the output side of the inverter 49. On the other hand, the vibrator-side electrodes 50C and 50D are connected to the ground portion and the power source portion of the inverter 49, respectively. The transducer side electrodes 50A, 50B, 50C, 50
Each connection between D and the inverter 49 is made by wiring such as a metal thin film.

Reference numeral 51 denotes a bonding metal portion formed on the bonding surface 43B of the vibrator substrate 43. The bonding metal portion 51
Is the first connecting metal portion 20 described in the first embodiment.
Substantially similar to the above, the vibrator substrate 4 is made of a metal material such as Ni
It is formed over the entire circumference along the frame shape of No. 3, and has a thickness that slightly projects downward from the oscillator substrate 43. The bonding metal part 51 is for bonding the oscillator substrate 43 and the integrated circuit board 23, and is welded onto the bonding metal part 29 of the integrated circuit board 23 by the solder film 30.

According to this embodiment having the above-described structure, the same effects as those of the first embodiment can be obtained. In particular, in this embodiment, the recess 43 is formed in the oscillator substrate 43.
Since the piezoelectric oscillator 41 according to the present embodiment has a structure in which A is formed and the vibrator 44 is provided inside the recess 43A,
Since the upper side of the oscillator substrate 43 is closed, the sealing member 35 described in the first embodiment can be omitted.

That is, in this embodiment, the oscillator 44 can be hermetically sealed only by joining the oscillator substrate 43 and the integrated circuit substrate 23, so that the number of parts is reduced and the manufacturing is simplified. Can be achieved.

In each of the above embodiments, the oscillator circuit 34 having the circuit configuration shown in FIG.
Although described as being configured in 1), the present invention is not limited to this. That is, the number of resistors and capacitors in the oscillator circuit, the type of CMOS circuit such as an inverter, and the like may be freely set depending on the oscillation frequency of the piezoelectric oscillator and the application. Accordingly, the oscillator substrate 12
(43) The number of electrodes provided on the integrated circuit board 23 and the number of external connection terminals such as the ground terminal 31 of the integrated circuit board 23 are increased or decreased.

In each of the above embodiments, the vibrator substrate 1 is used.
2 (43) and the integrated circuit board 23 and the vibrator substrate 12 and the sealing member 35 are welded by the solder films 30 and 37, but the present invention is not limited to this. Alternatively, means such as fusion bonding or solid phase diffusion bonding may be used.

Further, in each of the above-mentioned embodiments, the piezoelectric oscillator 10 (41) is mounted on the computer board and used as the clock pulse oscillator for the computer, but the piezoelectric oscillator according to the present invention is used. The oscillator can be widely used as an oscillator for other electronic devices.

[0066]

As described in detail above, according to the first aspect of the invention, the oscillation circuit including the piezoelectric vibrator, the first circuit portion and the second circuit portion can be formed as a single chip component. In addition, the mounting area can be significantly reduced.

According to the invention of claim 2, the piezoelectric vibrator on the side of the first substrate, the first circuit portion and the second circuit on the side of the second substrate.
Since the circuit part is connected by a plurality of electrodes, formation of metal thin film wiring, wire bonding, etc. are not required, and the manufacturing can be greatly simplified.

Further, according to the invention of claim 3, the second substrate is provided on one side of the first substrate in an overlapping manner, and the sealing member is provided on the other side of the first substrate in an overlapping manner. Thus, since the piezoelectric vibrator formed on the first substrate is sealed, it is not necessary to separately provide a sealing accommodating cover or the like and accommodate the piezoelectric oscillator in the accommodating cover or the like. As a result, the size of the piezoelectric oscillator can be greatly reduced.

[Brief description of drawings]

FIG. 1 is a perspective view showing a piezoelectric oscillator according to a first embodiment of the present invention.

FIG. 2 is an exploded perspective view showing the piezoelectric oscillator according to the first embodiment of the present invention in an exploded state.

FIG. 3 is a plan view showing a frame body according to the first embodiment.

FIG. 4 is a bottom view showing the frame body according to the first embodiment.

5 is a vertical sectional view taken along the line VV in FIG.

FIG. 6 is an enlarged vertical cross-sectional view showing essential parts of a vibration plate, a piezoelectric thin film, a metal thin film, and the like of the piezoelectric vibrator shown in FIG.

FIG. 7 is a plan view showing a base body according to the first embodiment.

FIG. 8 is a bottom view showing the base body according to the first embodiment.

9 is a vertical sectional view taken along the line IX-IX in FIG.

FIG. 10 is a vertical cross-sectional view showing a sealing member according to the first embodiment.

FIG. 11 is a bottom view of the sealing member according to the first embodiment.

FIG. 12 is a circuit diagram illustrating an oscillator circuit configured according to a first example.

FIG. 13 is a perspective view of an oscillator according to a second embodiment of the present invention.

FIG. 14 is a bottom view showing the lid body according to the second embodiment.

15 is a vertical cross-sectional view taken along arrow XV-XV in FIG.

FIG. 16 is a perspective view showing an integrated piezoelectric thin film functional device according to a conventional technique.

[Explanation of symbols]

10, 41 Piezoelectric oscillator 11 Frame body (first case part) 12,43 Transducer substrate (first substrate) 13,44 Piezoelectric oscillator 18,49 Inverter (first circuit portion) 19A, 19B, 19C, 19D, 50A, 50B, 5
0C, 50D Transducer side electrode 22 Base (second case part) 23 Integrated circuit board (second substrate) 24 CR circuit part (second circuit part) 27A, 27B, 27C, 27D Integrated circuit side electrode 34 Oscillation Circuit 35 Sealing member 42 Lid (first case portion)

Claims (3)

[Claims] 1. A first case part comprising a piezoelectric substrate and a first circuit part provided on a first substrate made of silicon, and a second case part.
To integrate the first and second case parts with the second case part in which the piezoelectric vibrator and the second circuit part to be electrically connected to the first circuit part are provided on the substrate. A piezoelectric oscillator comprising a piezoelectric vibrator, an oscillation circuit formed by the first circuit section and the second circuit section by bonding a second substrate to the first substrate. 2. A piezoelectric substrate and a first circuit portion on the side of the first substrate are electrically connected to a second circuit portion on the side of the second substrate so as to electrically connect the first circuit portion to the piezoelectric substrate. A side surface and another side surface of the second substrate facing the one side surface of the first substrate,
The piezoelectric oscillator according to claim 1, wherein a plurality of electrodes are provided respectively. 3. The piezoelectric oscillator according to claim 1, wherein a sealing member that seals the piezoelectric vibrator is provided on the other side surface of the first substrate.