JP3250366B2 - Piezoelectric oscillator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-precision and high-reliability piezoelectric oscillator having a built-in semiconductor integrated circuit, a piezoelectric vibrator, and electronic components, particularly for the field of communication equipment.

[0002]

2. Description of the Related Art An example of a conventional piezoelectric oscillator is shown in FIGS. 10A and 10B using a quartz oscillator as a piezoelectric oscillator, and FIGS. 11A and 11B. Description will be made using the crystal oscillator shown in the figure.

A plan view of FIG. 10A and a plan view of FIG.
As shown in the cross-sectional view, 42 Alloy (42% Ni
A semiconductor integrated circuit 103 such as a CMOS type is mounted on an island portion 102 of a lead frame 101 made of a highly conductive metal material such as a Fe alloy containing Cu or a Cu alloy with a conductive adhesive or the like. The pads of the integrated circuit 103 and the inner lead terminals 104 surrounding the periphery of the island portion 102 are electrically connected by Au wire bonding wires 105. The cylindrical crystal resonator 106 containing a rectangular AT crystal resonator piece is electrically connected to the inner leads 107 and 108 of the lead frame 101.
A plastic package type piezoelectric oscillator in which the lead frame 101, the semiconductor integrated circuit 103, the crystal oscillator 106, and the like configured as described above are transfer-molded with the resin 109 is generally used. Above all, Figure 10
Surface mount type (SM) as shown in [a] and 10 [b]
D) has become mainstream.

FIG. 11A is a plan view and FIG.
As shown in the cross-sectional view of [b], a semiconductor integrated circuit 12 of a CMOS type or the like is provided in a case 121 formed of a multilayer ceramic substrate in which metal wiring is metallized on the inner and outer surfaces.
2 is mounted with a conductive adhesive or the like, and the pads of the semiconductor integrated circuit 122 and the lands 123 of the metal wiring metallized on the case 121 are electrically connected by Au or Al wire bonding wires 124. Then, the rectangular AT crystal resonator element 125 is arranged above the semiconductor integrated circuit 122 in parallel with the surface of the semiconductor integrated circuit 122, and is electrically mounted on the mount part 126 for the AT crystal resonator element 125 formed in the case 121. The connection is fixed. Then, a metal lid 127 is attached to the case 121.
Have been recently developed and introduced to the market by joining together by glass frit or seam welding and hermetically sealing.

[0005]

Electronic components used in mobile communication devices such as mobile phones and pagers, communication devices such as PHP (personal handy horn), and industrial devices such as automobiles are known. It must have high precision, high quality, and high reliability, and must have characteristics that can withstand harsh environments. That is, the piezoelectric oscillator, which is the reference oscillation source of those devices, is required to have high accuracy, high quality, and high reliability, and the frequency accuracy is several ppm or less (for example, ± 3 ppm or less, further ± 1 ppm or less), and Is required to have a high accuracy of 0.1 ppm or less. For the reliability of long-term aging, for example, it is required to guarantee that the frequency deviation for 10 years or more is several ppm or less.

In the conventional crystal oscillator shown in FIG. 10, the lead 110 of the crystal unit 106 and the gate and drain of the semiconductor integrated circuit 103 are connected to the inner lead 10.
7, 108. As shown, the inner leads 107 and 108 are wired in parallel, and a resin 109 is molded between them. It is generally known that a capacitance is generated between the parallel electrodes as described above, and the generated wiring capacitance Cα of the lead frame is given by the following equation.

[0007]

(Equation 1)

Ε ₀ : dielectric constant in vacuum = 8.855 ×
10 ⁻¹⁵ F / mm ε _S : relative dielectric constant of the molding material S: opposing surface area of the lead frame d: interval between the lead frames That is, in the crystal oscillator shown in FIG. And the load capacitance between the gate and the drain of the semiconductor integrated circuit. That is, the capacitances C ₀ , C ₁ , C _L, and C α of the equivalent circuit including the crystal oscillator and its oscillation circuit shown in FIG. 12 affect the oscillation frequency of the crystal oscillator, and its frequency change rate (unit: ppm) ) Is shown by the following equation.

[0009]

(Equation 2)

DF / F: Rate of change of frequency C ₀ : Parallel capacitance of crystal unit C ₁ : Equivalent series capacitance of crystal unit C _L : Load capacitance Cα: Wiring capacity By the way, when resin is placed under high humidity, moisture is generated. To absorb moisture. As a result, the dielectric constant of the resin increases, and as a result, the wiring capacitance Cα before moisture absorption increases. The amount of the increase depends on the difference in the moisture absorption of the resin, the thickness of the resin package of the crystal oscillator, and the like, but it has been experimentally confirmed that the increase is about 1.5 to 2 times that before the moisture absorption. When the frequency change rate dF / F of Expression 2 is calculated based on this value, about -3
ppm to -6 ppm, and the frequency shifts in the negative direction.

As described above, the frequency of the crystal oscillator changes on the order of several ppm due to the change in the wiring capacitance Cα due to moisture absorption, and there is a problem that a communication error occurs in a communication device.

In the piezoelectric oscillator shown in FIG. 11, a quartz oscillator piece is directly mounted on a case formed of a laminated insulating substrate such as ceramic. In order to ensure high precision and high reliability, seam welding is used for sealing. However, at the time of seam welding, high heat of about 200 ° C. to 300 ° C. is locally generated at the interface between the metallic lid and the case to be sealed. There is a problem that the vibrator element receives thermal stress from the lid and the case, and the vicinity of the mount of the vibrator element is distorted in a concave shape, thereby changing the frequency.

Also, when mounting on a substrate of a communication device or the like by solder reflow or the like, there is also a problem in that thermal stress and strain are similarly generated in the crystal resonator piece, thereby causing a frequency change. It has been experimentally confirmed that these frequency change rates also occur on the order of several ppm.

Further, as shown in FIG. 11, a crystal resonator element is disposed directly above the semiconductor integrated circuit, and the heat generated in the semiconductor integrated circuit with the increase in the frequency of the crystal oscillator and the high integration of the semiconductor integrated circuit. As a result, the temperature at the center of the crystal resonator element increases. As a result, there is also a problem that the oscillation frequency of the crystal oscillator changes. This is the most important issue in terms of reliability, particularly when used in equipment having a severe operating temperature environment such as automobiles or communication equipment.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art, and an object of the present invention is to provide a small, thin, highly accurate and highly reliable surface mount piezoelectric oscillator. The goal is to provide a good yield at low cost.

[0016]

A piezoelectric oscillator according to the present invention.
Is a piezoelectric oscillator having a built-in semiconductor integrated circuit and a piezoelectric vibrator, wherein the semiconductor integrated circuit is mounted on a first surface of a case formed of a laminated insulating substrate including a metal wiring therein, and the semiconductor integrated circuit is formed by wire bonding. The piezoelectric vibrator is electrically connected to a land of metal wiring formed on the first surface of the case, and the piezoelectric vibrator is arranged on the first surface of the case in parallel with the semiconductor integrated circuit, and formed on the case. The piezoelectric vibrator is positioned at a land portion that connects the piezoelectric vibrator, and an electrode of the piezoelectric vibrator and the land portion are electrically connected, and an external electrode terminal electrically connected to the semiconductor integrated circuit, Formed on the outer surface of the case, further sealing the case with a lid, electrically connected to the semiconductor integrated circuit,
Signal input for controlling data of the semiconductor integrated circuit from outside
Force terminal on the second surface having a step with the back surface of the case
It is characterized by having been formed .

According to the present invention, there is provided a piezoelectric oscillator including a semiconductor integrated circuit, a piezoelectric vibrator, and an electronic component, wherein the semiconductor integrated circuit is formed of a laminated insulating substrate including metal wiring therein. It is mounted on one surface and is electrically wired to lands of metal wiring formed on the first surface of the case by wire bonding, and the electronic component is arranged at least on the first surface or the second surface of the case Electrically connected to the semiconductor integrated circuit by metal wiring, the piezoelectric vibrator is disposed on the first surface of the case in parallel with the semiconductor integrated circuit and the electronic component, and formed on the case. The piezoelectric vibrator is positioned at a land for connection, and the electrode of the piezoelectric vibrator and the land are electrically connected to each other and electrically connected to the semiconductor integrated circuit. The external electrode terminals, are formed on the outer surface of the case, further sealed case with a lid, the semiconductor
The semiconductor integrated circuit is electrically connected to an integrated circuit and externally connected to the semiconductor integrated circuit.
The signal input terminal for controlling the circuit data is
May be formed on the second surface having a step with the back surface of
No.

[0018]

[0019]

Further , in the above configuration , at least one projection may be formed on the first surface of the case, and the hermetically sealed piezoelectric vibrator may be positioned by the projection.

Further , the piezoelectric vibrator may be configured as a crystal vibrator or a SAW resonator housed in a cylindrical case.

The piezoelectric vibrator may be configured as a crystal resonator or a SAW resonator housed in a box-shaped case.

The piezoelectric vibrator formed in the case is
It is preferable that a groove is formed in the land portion to be connected .

The upper surface of the projection and the land may be formed on the same plane.

The case may be constituted by a laminated ceramic substrate having metallized metal wirings inside and outside.

[0026]

[0027]

[0028]

[0029]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the piezoelectric oscillator of the present invention will be described with reference to the drawings, taking as an example a quartz oscillator of a surface-mounted multilayer ceramic package using a quartz oscillator built in a cylindrical case for a piezoelectric oscillator. .

Embodiment 1 FIGS. 1, 2, 3, and 4 are a structural diagram and a circuit configuration diagram of an embodiment of a piezoelectric oscillator according to the present invention.

As shown in the plan view of FIG. 1A, the sectional view of FIG. 1B and the side view of FIG.
A case 1 formed of a multilayer ceramic insulating substrate, which is printed with a metal wiring material such as o (one method of metallization), and plated with Ni or Au, etc.
A CMOS type semiconductor integrated circuit (IC chip: hereinafter referred to as IC chip) 2 shown in FIG. 1 of JP-A-2-170703 is mounted on a first surface 4 of a case 1 by a conductive adhesive 3 or the like. , IC chip 2 pad and IC
The land 5 of the metal wiring surrounding the chip 2 is electrically connected by an Au or Al wire bonding wire 6. A cylinder type crystal resonator 8 having a built-in rectangular AT crystal resonator piece 7 has a lead 9 connected to an IC.
A case 1 electrically connected to a gate terminal 10 and a drain terminal 11 for oscillating a crystal resonator 8 of a chip 2 by an Au or Al wire bonding wire 6.
Are fixed with high melting point solder having a melting point of about 300 ° C. and are electrically connected at the same time.

The crystal oscillator 8 is connected to the IC chip 2 by the projections 13a and 13b provided on the first surface 4 of the case 1.
Is positioned on the first surface 4 of the case 1 in parallel with Here, the land 12 connecting the lead 9 of the crystal unit 8 and the surfaces of the projections 13a and 13b are flush with each other. There is an advantage that the parts are common.

The land 12 connecting the lead 9 of the crystal unit 8 has a groove 14 as shown in FIG. 1A. Although not shown here, the lead 9 of the crystal unit 8
May be bent and connected to the land portion 12.

As shown in FIG. 1A and FIG. 3, DIN (Data)
Terminals for signal input of an In) terminal 15 and a WR (Write) terminal 16 are provided in a line. Here, the signal input terminals 15 and 16 correspond to the DIN and WR terminals of the IC chip 2 and the Au or Al wire bonding wires 6 respectively.
Are electrically connected to each other.

Here, the signal input terminals 15 and 16 may be formed in any direction of the case 1 and may be formed on any surface.

Further, Case 1 is made of Kovar or 42 Alloy.
Such as metal or ceramic or resin lid 17
Seal with. Here, the sealing method may be seam welding or adhesive fixing with an adhesive or the like.

Then, the sealed case 1 is set on the jig of the data control device 31 as shown in FIG. The contact probe 32 of the data control device 31 is brought into contact with the power terminals 18 and 19, the output terminal 20 and the signal input terminals 15 and 16 of the case 1. As a result, a serial data signal is input from the data control device 31, and the data is written to the IC chip 2 built in the case 1, whereby the oscillation frequency (F ₀ ) of the crystal oscillator is adjusted with high precision.

FIG. 4 shows an embodiment of the frequency adjusting method. Here, the direction in which the contact probe 32 is brought into contact is not limited to this embodiment, but may be from any direction. Alternatively, a plurality of crystal oscillators may be arranged in the data control device 31 to adjust the frequency simultaneously. The setting direction of the crystal oscillator in the jig portion of the data control device 31 may be either front or back of the case 1.

According to the above-described structure, the crystal resonator element has a structure that does not directly receive stress from the case and is kept air-tight, and the wiring (lead frame) capacitance Cα of the crystal resonator changes due to humidity. Since the structure does not change, a highly accurate and highly reliable crystal oscillator having a frequency change rate (frequency accuracy) of several ppm or less (the frequency accuracy of this embodiment is approximately ± 3 ppm at a normal temperature of 25 ° C.) can be obtained. . Further, since the crystal unit is arranged in parallel with the IC chip,
The heat generated by the heat generated by the C chip is conducted to the case and released to the outside. Therefore, the quartz oscillator piece is not directly heated, and the temperature of the quartz oscillator piece does not increase.

Embodiment 2 FIGS. 5A and 5B are structural views showing a second embodiment of the piezoelectric oscillator according to the present invention . In the first embodiment, a chip capacitor 41 is provided on the first surface 4 of the case 1.
Alternatively, a chip resistor 42 and the like are arranged in parallel with the crystal unit 8, and the variable capacitance diode 4 is further provided on the second surface 43 of the case 1.
This is a crystal oscillator in which 4 and the like are arranged. This type of crystal oscillator can change the oscillation frequency by voltage control. Then, similarly to the first embodiment, the data of the IC chip 45 is controlled from each signal input terminal.

According to the above-described structure, the quartz-crystal vibrating piece has a structure that is not directly subjected to stress from the case and is kept airtight, and a structure in which the wiring capacitance Cα of the quartz-crystal vibrating does not change due to humidity. As a result, a highly accurate and highly reliable voltage controlled crystal oscillator having a frequency accuracy of several ppm or less can be obtained. Further, since the crystal oscillator is arranged in parallel with the IC chip, heat generated by the heat of the IC chip is conducted to the case and released to the outside. Therefore, the quartz oscillator piece is not directly heated, and the temperature of the quartz oscillator piece does not increase.

Third Embodiment FIG. 6 is a structural view showing a main part of a first embodiment of a piezoelectric oscillator according to the present invention . FIG. 6 shows an embodiment in which signal input terminals 15 and 16 that are electrically connected to the IC chip 2 and control data of the IC chip 2 from the outside are formed on the second surface 43 of the case 1.

According to the above-described configuration, since each signal input terminal is formed on the second surface of the case, a step with respect to the back surface of the case can be ensured. Can be prevented from short-circuiting with the wiring.

Embodiment 4 FIG. 7 is a structural diagram showing a third embodiment of the piezoelectric oscillator according to the present invention . In this embodiment, a quartz oscillator 51 in which an AT quartz oscillator piece 8 is built in a box-shaped ceramic or metal case is used as the piezoelectric oscillator. Here the crystal oscillator 5
One electrode is formed on the back surface of the box-shaped case.

According to the above-described structure, the crystal resonator element is kept airtight, and the wiring capacitance C of the crystal resonator is maintained.
Since α is not changed by humidity, a highly accurate and highly reliable crystal oscillator having a frequency accuracy of several ppm or less can be obtained. Further, as shown in FIG. 7, the box-shaped case is thinner than the cylinder type, so that the crystal oscillator incorporating the case can be made thinner.

Fifth Embodiment FIGS. 8 and 9 are structural views showing a fourth embodiment of the piezoelectric oscillator according to the present invention . FIG. 8 shows a SA in which a SAW resonator element 61 is built in a cylinder type case in a piezoelectric vibrator.
FIG. 9 shows an embodiment using a W resonator 62, and FIG. 9 shows an embodiment using a SAW resonator 63 built in a box-shaped ceramic or metal case.

As described above, by positioning the SAW resonators 62 and 63 of the cylinder type or box type having the same shape as the crystal unit on the first surface 4 of the case 1, the SAW resonators 62 and 63 are formed. 100M using 63
A highly accurate and highly reliable SAW oscillator for a high frequency band such as Hz to 500 MHz can be obtained.

[0048]

According to the present invention, the piezoelectric vibrator piece has a structure which does not directly receive stress from the case and is hermetically sealed, and has a structure in which the wiring capacitance Cα of the piezoelectric vibrator does not change due to humidity. Frequency accuracy is a few ppm
This has the effect of obtaining a highly accurate and highly reliable piezoelectric oscillator as described below. Further, since the semiconductor integrated circuit and the piezoelectric vibrator are arranged in parallel, they are not directly affected by the self-heating of the semiconductor integrated circuit. Therefore, there is an effect that a highly reliable piezoelectric oscillator having no frequency change due to the use environment can be obtained. In particular, in the present invention, semiconductor integration
A signal input means for writing data to the circuit is provided in the case.
Frequency adjustment after the completion of the piezoelectric oscillator.
This has the effect that it can be performed easily and easily. Thereby high
The effect of improving the yield when adjusting the frequency to accuracy
It also has fruit. Form the signal input terminal on the second surface of the case.
As a result, a step with the lower surface of the case can be secured,
When mounting the vibrator, show with wiring of the board of communication equipment etc.
Can be prevented.

According to the second aspect of the present invention, the piezoelectric vibrator piece has a structure that does not directly receive stress from the case and is hermetically sealed, and the wiring capacitance Cα of the piezoelectric vibrator does not change due to humidity. Because of the structure, a voltage control type piezoelectric oscillator having a high frequency accuracy of several ppm or less and a high reliability can be obtained. Further, since the semiconductor integrated circuit and the piezoelectric vibrator are arranged in parallel, they are not directly affected by the self-heating of the semiconductor integrated circuit. Therefore, there is an effect that a highly reliable piezoelectric oscillator having no frequency change due to the use environment can be obtained. The invention
In particular, data is externally transmitted to the semiconductor integrated circuit.
By providing a signal input means for writing in the case
Frequency adjustment after the completion of the piezoelectric oscillator
It has the effect of being able to do it. This enables high-precision frequency
This also has the effect of improving the yield when adjusting.
Since the signal input terminal is formed on the second surface of the case,
The step with the lower surface of the electrode can be secured, and the piezoelectric oscillator is mounted.
When doing so, prevent short-circuits with the wiring of the board of communication equipment, etc.
Can be.

[0050]

[0051]

[0052] According to the third aspect of the present invention, by forming a protrusion on the first surface of the case, of course the positioning of the piezoelectric vibrator of the cylinder type or a rectangular case, the piezoelectric from the impact caused by dropping or the like of the piezoelectric oscillator It plays the role of protecting the oscillator. Further, since the piezoelectric vibrator is hermetically sealed, the vibration of the piezoelectric vibrator is stabilized and a high quality piezoelectric oscillator can be provided.

[0053]

According to the fourth aspect of the present invention, by using a cylinder type quartz oscillator for the piezoelectric oscillator,
An inexpensive piezoelectric oscillator with high reliability can be provided. Further, by using a cylinder type SAW resonator as the piezoelectric vibrator, a highly reliable and inexpensive piezoelectric oscillator for a high frequency band can be provided.

According to the fifth aspect of the invention, a thin and highly reliable piezoelectric oscillator can be provided by using a box-shaped case crystal oscillator as the piezoelectric oscillator. Further, by using a box-shaped SAW resonator as the piezoelectric vibrator, a thin, highly reliable and inexpensive piezoelectric oscillator for a high frequency band can be provided.

[0056]

[0057]

According to the sixth aspect of the present invention, by providing a groove in the land portion formed on the first surface of the case for connecting the piezoelectric vibrator, unnecessary high melting point solder is not required when mounting the piezoelectric vibrator. This has an effect of preventing the piezoelectric vibrator from flowing into the groove and short-circuiting. It also has the effect of reducing stress from the case due to heat such as solder reflow and preventing solder cracks in the mount.

According to the seventh aspect of the present invention, the upper surface of the projection formed on the case and the land portion connecting the piezoelectric vibrator are formed on the same plane, so that the alumina is laminated and sintered integrally. In this case, the laminated portion is common in the manufacture of the semiconductor device, and the manufacturing cost can be reduced.

According to the eighth aspect of the present invention, since the case is formed of a multilayer ceramic substrate, a case having good heat dissipation and good moisture resistance can be provided, and a highly accurate and highly reliable piezoelectric oscillator can be provided.

[Brief description of the drawings]

FIG. 1 is a structural view showing one embodiment of a piezoelectric oscillator of the present invention.

FIG. 2 is a side view showing one embodiment of the piezoelectric oscillator of the present invention.

FIG. 3 is a circuit diagram showing an embodiment of a piezoelectric oscillator according to the present invention.

FIG. 4 is a layout diagram in which the piezoelectric oscillator of the present invention is set in a data control device.

FIG. 5 is a structural view showing another embodiment of the present invention.

FIG. 6 is a structural view showing a main part of one embodiment of the piezoelectric oscillator of the present invention.

FIG. 7 is a structural view showing another embodiment of the present invention.

FIG. 8 is a structural view showing another embodiment of the present invention.

FIG. 9 is a structural view showing another embodiment of the present invention.

FIG. 10 is a structural view showing a conventional piezoelectric oscillator.

FIG. 11 is a structural view showing a conventional piezoelectric oscillator.

FIG. 12 is an equivalent circuit diagram of a conventional piezoelectric oscillator.

[Explanation of symbols]

 Reference Signs List 1 case 2 semiconductor integrated circuit (IC chip) 3 conductive adhesive 4 first surface 5 land 6 wire bonding wire 7 AT crystal resonator piece 8 crystal resonator 9 lead 10 gate terminal 11 drain terminal 12 land 13a, 13b protrusion 14 groove 15 DIN terminal 16 WR terminal 17 lid 18, 19 power supply terminal 20 output terminal 31 data control device 32 contact probe 41 chip capacitor 42 chip resistor 43 second surface 44 variable capacitance diode 45 IC chip 51 crystal oscillator 61 SAW resonator Pieces 62, 63 SAW resonator 101 Lead frame 102 Island section 103 Semiconductor integrated circuit 104 Inner lead terminal 105 Wire bonding wire 106 Crystal resonator 107, 108 Inner lead 109 Resin 110 Lead 121 Case 122 Semiconductor integrated circuit 123 Land 124 Wire bonding wire 125 AT crystal oscillator piece 126 Mounting part 127 Lid

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI H03H 9/64 H03H 9/64 A (56) References JP-A-3-19406 (JP, A) JP-A-4-3609 ( JP, A) JP-A-59-183508 (JP, A) JP-A-3-244208 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H03B 5/32 H03H 9/02 H03H 9/10 H03H 9/64

Claims (8)

(57) [Claims] 1. A piezoelectric oscillator incorporating a semiconductor integrated circuit and a piezoelectric vibrator, wherein the semiconductor integrated circuit is mounted on a first surface of a case formed of a laminated insulating substrate including metal wiring inside, and a wire is provided. The piezoelectric vibrator is electrically connected to a land of metal wiring formed on the first surface of the case by bonding, and the piezoelectric vibrator is arranged on the first surface of the case in parallel with the semiconductor integrated circuit, An external electrode terminal electrically connected to the semiconductor integrated circuit, wherein the electrode is positioned on a land portion connecting the piezoelectric vibrator formed on the semiconductor device, and an electrode of the piezoelectric vibrator is electrically connected to the land portion. and is formed on an outer surface of the casing, it is further sealed case with a lid, electrically connected to said semiconductor integrated circuit, the external
A signal input terminal for controlling data of the semiconductor integrated circuit,
A piezoelectric oscillator formed on a second surface having a step with the back surface of the case . 2. A piezoelectric oscillator incorporating a semiconductor integrated circuit, a piezoelectric vibrator, and an electronic component, wherein the semiconductor integrated circuit is mounted on a first surface of a case formed of a laminated insulating substrate including metal wiring inside. And electrically wired to a land of metal wiring formed on the first surface of the case by wire bonding, wherein the electronic component is disposed on at least the first surface or the second surface of the case, and a metal wiring The piezoelectric vibrator is disposed on the first surface of the case in parallel with the semiconductor integrated circuit and the electronic component, and the piezoelectric vibrator formed on the case is electrically connected to the semiconductor integrated circuit. The electrodes of the piezoelectric vibrator and the lands are electrically connected to each other, and are electrically connected to the semiconductor integrated circuit. Electrode terminals, are formed on the outer surface of the casing, it is further sealed case with a lid, electrically connected to said semiconductor integrated circuit, the external
A signal input terminal for controlling data of the semiconductor integrated circuit,
A piezoelectric oscillator formed on a second surface having a step with the back surface of the case . 3. The method according to claim 1, wherein at least one projection is formed on the first surface of the case, and the hermetically sealed piezoelectric vibrator is positioned by the projection.
Or the piezoelectric oscillator according to 2. 4. A piezoelectric oscillator according to claim 3, wherein the piezoelectric vibrator is been crystal oscillator or SAW resonator incorporated in the cylinder-shaped case. 5. The piezoelectric oscillator according to claim 3, wherein the piezoelectric vibrator is a box-type crystal oscillator built in the case or SAW resonators. 6. The piezoelectric oscillator according to claim 4, characterized in that a groove is formed in the land portion. 7. A top surface of the projection, a piezoelectric oscillator according to claim 4, wherein the land portion is characterized in that it is formed in the same plane. 8. The method of claim 1 or 2 piezoelectric oscillator, wherein it is constituted by a multilayer ceramic substrate on which the case is metallized metal wire inside and outside.