JPH0746072A - Manufacture of crystal resonator - Google Patents

Abstract

PURPOSE:To provide a manufacturing method capable of mass-producing crystal resonators provided with the basic vibration number of higher than 100MHz with improved yield by solving a problem that it is difficult to grind a crystal for vibration down to under 30mum in the crystal resonators used in many ways as oscillators and filters for communications equipment or the like. CONSTITUTION:After the crystal plate 1 for the vibration is directly jointed on a substrate 2 and both surfaces are simultaneously ground, a through-hole is provided on the substrate 2 and an excitation electrode 3 is formed. By directly jointing the crystal plate 1 on the thick substrate 2 without deflection, since grinding can be performed with a thick carrier, the crystal plate 1 can be ground to less than 15mum while maintaining flatness, parallelism and surface roughness required for a crystal device.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a crystal resonator, and more particularly to a method for manufacturing a crystal resonator having a fundamental frequency of 100 MHz or more of thickness shear vibration.

[0002]

2. Description of the Related Art Crystal oscillators are widely used as oscillators and filter elements in communication equipment and the like because of their excellent resonance characteristics. In recent years, there has been a trend toward higher frequencies due to congestion of communication circuits and high-quality communication.

FIG. 11 is a diagram showing a conventional crystal resonator. The crystal unit comprises, for example, a disk-shaped crystal plate 1 that is AT-cut. The excitation electrode 3 and the extraction electrode 6 are formed on both main surfaces of the crystal plate 1. Normally, the outer peripheral portions of the extended ends of the extraction electrode 6 are held and sealed by a structure not shown. Then, it is excited by an oscillating circuit (not shown) and exhibits a thickness shear vibration that is displaced between the two principal surfaces in opposite directions.

Such thickness shear vibration is inversely proportional to the thickness t, and the smaller the thickness, the higher the vibration frequency f. That is, f = k / t (where k is a piezoelectric constant and is usually 1670
MHz · μm). For example, when the vibration frequency is 10 MHz, a thickness of 167 μm is required.
The vibration frequency is the fundamental vibration wave, and so on.
Then, in general, both sides are polished and processed to have the same thickness.

As a method for thinning the vibrating quartz plate, there is one described in Japanese Patent Laid-Open No. 3-116882.
This polishing method will be described with reference to FIG. Figure 12 (a)
Is an exploded view of the composite plate, FIG. 7B is a side view of the composite plate before polishing, FIG. 7C is a side view of the composite plate after polishing, and FIG.
3 is a cross-sectional view of a crystal oscillator, in which 1 is a crystal plate, 3 is an excitation electrode, and 7 is a reinforcing plate. In order to polish the crystal plate 1, a reinforcing plate 7 having a through hole is adhered to one main surface of the crystal plate 1 as shown in FIG. 2B, and the other main surface is attached as shown in FIG. After polishing, the excitation electrode 3 is provided as shown in FIG.

[0006]

By the way, in the crystal unit, when a crystal unit of 100 MHz is to be obtained, the thickness of the crystal plate becomes 16.7 μm. However, in the double-sided polishing of the crystal plate, in addition to the problem of the thickness of the carrier used, it is difficult to polish the crystal plate to 30 μm or less because the crystal plate is bent, distorted or damaged. Also in single-sided polishing, similar to double-sided polishing, when the crystal plate becomes 30 μm or less in thickness, in addition to the problem that the crystal plate is bent or distorted, the wax used when the crystal plate is bonded to the polishing table, The flatness, parallelism, and surface roughness such as the variation in the thickness of the quartz plate after polishing due to the variation in the thickness of the epoxy adhesive, and the scratches and distortions on the surface of the quartz plate that is attached to the polishing table due to the adhesive. Is extremely important for various electrical characteristics and is not preferable for polishing a quartz plate. Even if it could be processed, there is a problem with the holding part of the crystal plate.
The limit was a crystal unit with m 2 and a vibration frequency of 55 MHz. Further, the polishing method of JP-A-3-116882 is basically a polishing method using an adhesive, and the above-mentioned problem of single-sided polishing occurs.

In view of the above, the present invention provides a vibrating crystal plate having the flatness, parallelism, and surface roughness required for a crystal device.
It is an object of the present invention to provide a method for manufacturing a crystal unit, which can be mass-produced with a crystal unit having a vibration frequency of 100 MHz or higher by polishing to a size of 5 μm or less and with high yield.

[0008]

In order to achieve the above-mentioned object, a method of manufacturing a crystal unit according to the present invention is a method of directly bonding a vibrating crystal plate to a substrate, performing simultaneous double-side polishing, and providing a through hole.
The electrode is provided so as to excite the portion corresponding to the through hole.

[0009]

According to the present invention, as shown in the above method, since the vibrating crystal plate is directly bonded on the thick substrate without bending, polishing with a thick carrier is possible, and it is directly bonded on the substrate by some polishing. Since the existing crystal plate for vibration can be made extremely thin, the vibration frequency can be increased.

Further, since the bonding thickness is zero, the variation in the thickness of the vibrating quartz plate after polishing due to the use of an adhesive, which is a problem of single-sided polishing, and the flatness, parallelism, and surface roughness. Deterioration can be eliminated and various electrical characteristics can be improved.

[0011]

EXAMPLE 1 FIG. 1 is a diagram showing Example 1 of the present invention. In the figure, 1 is a crystal plate for vibration, 2 is a substrate made of a glass plate, and 3 is an excitation electrode.

A crystal plate for vibration 1 whose both sides are mirror-polished up to 50 μm at 1 cm square and a glass substrate 2 whose both surfaces are mirror-polished up to 1 mm at 1 cm square are a crystal device and flatness and parallelism necessary for direct bonding. , Are bonded by the direct bonding technique while maintaining the surface roughness (FIG. 1 (b)). Direct bonding is a direct bonding of crystal and glass without the use of an adhesive. After the contact surface between the crystal plate 1 and the glass substrate 2 is sufficiently cleaned, a hydrophilizing treatment is performed with a mixed solution of hydrogen peroxide solution, ammonia and pure water, and contact is made by the intermolecular force of water molecules. After that, when heat treatment is performed at 100 ° C. to 600 ° C., water molecules are removed and sufficient strength is obtained for bonding and polishing by intermolecular force.

After the crystal plate 1 and the glass substrate 2 are directly bonded, both surfaces are polished together with the glass substrate 2 until the crystal plate 1 becomes 15 μm (FIG. 1 (c)), and the glass substrate 2 is hollowed out by etching with hydrofluoric acid. Then, 800 Å of chromium and 3000 Å of gold were vapor-deposited as the excitation electrode 3 (FIG. 1 (d)).

In the conventional mass-produced crystal oscillator, the vibration frequency is limited to 55 MHz, but in this embodiment,
Since the crystal plate 1 and the glass substrate 2 are directly bonded and both surfaces are polished, the bonding thickness is zero and a thick carrier can be used, so that the flatness, parallelism, and surface roughness required for the crystal device are maintained. As it is, the vibrating crystal plate can be polished to 15 μm or less.

From this example, as shown in FIG. 2, a vibration frequency of 100 MHz or more could be obtained. (Embodiment 2) FIG. 2 is a diagram showing Embodiment 2 of the present invention.
In the figure, 1 is a crystal plate for vibration, 2 is a substrate made of a silicon plate, and 3 is an excitation electrode.

The crystal plate 1 whose both sides are mirror-polished up to 50 μm at 1 cm square and the silicon substrate 2 whose both sides are mirror-polished up to 0.5 mm at 1 cm square are a crystal device and flatness, parallelism necessary for direct bonding, They are bonded by the direct bonding technique while maintaining the surface roughness (Fig. 2 (b)). Direct bonding is the direct bonding of quartz and silicon without the use of an adhesive. After the contact surface between the crystal plate 1 and the silicon substrate 2 is sufficiently cleaned, a hydrophilization treatment is performed with a mixed solution of hydrogen peroxide solution, ammonia and pure water, and contact is made by the intermolecular force of water molecules. After that, when heat treatment is performed from 100 ° C. to 500 ° C., water molecules escape, and sufficient strength is obtained for bonding and polishing by intermolecular force.

After that, the quartz plate 1 was polished on both sides together with the silicon substrate 2 until it became 15 μm (FIG. 2 (c)), the silicon substrate 2 was hollowed and etched by hydrazine, and the excitation electrode 3 was made of chromium 800 Å and gold 3000 Å.
It vapor-deposited (FIG.2 (d)). According to this method, in the conventional mass-producible crystal oscillator, the vibration frequency was limited to 55 MHz, but 100 MHz or more could be obtained. (Embodiment 3) FIG. 4 is a diagram showing Embodiment 3 of the present invention.
In the figure, 1 is a crystal plate for vibration, 2 is a first substrate made of a silicon plate, 3 is an excitation electrode, 4 is a second substrate made of a crystal plate,
Reference numeral 6 is an extraction electrode, and 8 is a groove.

The crystal plate 1 whose both sides are mirror-polished up to 50 μm at 1 cm square and the silicon substrate 2 whose both sides are mirror-polished up to 500 μm at 1 cm square are the flatness, parallelism and surface roughness required for the crystal device and direct bonding. It is adhered by the direct joining technique while maintaining the thickness (Fig. 4 (b)). After that, double-side polishing is performed together with the silicon substrate 2 until the crystal plate 1 becomes 15 μm (FIG. 4 (c)), and a depth of 3 is formed on the non-bonded surface of the crystal plate 1.
A quartz substrate 4 having a groove of 000 Å and embedded with excitation electrodes of chromium and gold is directly bonded (FIG. 4 (d)).
The silicon substrate is removed by etching with hydrazine, and chromium is 800 Å and gold is 3000 as the excitation electrode 3.
Å Evaporated (Fig. 4 (e)).

In the conventional mass-producible crystal oscillator, the vibration frequency was limited to 55 MHz, but it was possible to obtain a vibration frequency of 100 MHz or more from this embodiment. Further, in this embodiment, by transferring the vibrating crystal plate to the second substrate, it is possible to carry out batch processing and improve the processing accuracy of the holding substrate. (Embodiment 4) FIG. 5 is a diagram showing Embodiment 4 of the present invention.
In the figure, 1 is a crystal plate for vibration, 2 is a first substrate made of a glass plate, 3 is an excitation electrode, 4 is a second substrate made of a silicon plate, 6 is an extraction electrode, 8 is a groove, and 9 is a bump. .

The crystal plate 1 whose both sides are mirror-polished up to 50 μm at 1 cm square and the glass substrate 2 whose both surfaces are mirror-polished up to 500 μm at 1 cm square are the flatness, parallelism and surface roughness required for the crystal device and direct bonding. It is adhered by the direct joining technique while maintaining the thickness (Fig. 5 (b)). After that, after polishing both sides with the crystal substrate 2 until the crystal plate 1 becomes 15 μm, chromium is 600 Å and gold is 1 as the excitation electrode 3.
400Å is vapor-deposited (FIG. 5 (c)), and the silicon substrate 4 having a groove with a depth of 3000Å and a lead electrode of chrome and gold and a buried bump is directly bonded to the non-bonded surface of the crystal plate 1 (FIG. (D)) After that, the glass substrate is removed by etching with hydrofluoric acid, and chromium is used as the excitation electrode to 600 nm.
Å, 1400Å gold was vapor deposited (Fig. 5 (e)).

In the conventional mass-producible crystal oscillator, the vibration frequency was limited to 55 MHz, but it was possible to obtain a vibration frequency of 100 MHz or more according to this embodiment. (Embodiment 5) FIG. 6 is a diagram showing Embodiment 5 of the present invention.
In the figure, 1 is a crystal plate for vibration, 2 is a first substrate made of a silicon plate, 3 is an excitation electrode, 4 is a second substrate made of a glass plate, 6 is an extraction electrode, and 8 is a groove.

The crystal plate 1 whose both sides are mirror-polished up to 50 μm at 1 cm square and the silicon substrate 2 whose both sides are mirror-polished up to 500 μm at 1 cm square are the flatness, parallelism and surface roughness required for the crystal device and direct bonding. It is adhered by the direct joining technique while maintaining the same (FIG. 6 (b)). afterwards,
Both sides were polished until the crystal plate 1 became 15 μm (Fig. 6
(C)) A glass substrate 4 having a groove with a depth of 3000 Å and a chrome and gold excitation electrode 3 embedded therein is directly bonded to the non-bonded surface of the quartz plate 1 (FIG. 6 (d)), and is etched with hydrazine. The silicon substrate 2 was removed by means of vacuum, and 800 Å of chromium and 3000 Å of gold were vapor-deposited as excitation electrodes (Fig. 6).
(E)).

In the conventional mass-producible crystal oscillator, the vibration frequency was limited to 55 MHz, but it was possible to obtain a vibration frequency of 100 MHz or more according to this embodiment. Further, in this embodiment, since the vibrating crystal plates are directly bonded to both surfaces of the substrate and both surfaces are polished, the yield is improved.

In Examples 3 to 5, silicon, glass and silicon were used as the first substrate and quartz, silicon and glass were used as the second substrate, but glass and silicon were used as the first substrate, and quartz and silicon were used as the second substrate. The same effect can be obtained when any of the glass and the glass is used. Moreover, even if the vibrating crystal plate is directly bonded to one surface of the first substrate or both surfaces are directly bonded, the thickness of the bonded portion is zero and polishing can be performed with a thick carrier.
It can be polished to m or less and a vibration frequency of 100 MHz or more can be obtained. The first substrate material and the second substrate material must be different. (Sixth Embodiment) FIG. 7 is a diagram showing a sixth embodiment of the present invention.
In the figure, 1 is a quartz plate for vibration, 2 is a first substrate made of a quartz plate, 3 is an excitation electrode, 4 is a second substrate made of a quartz plate, and 5 is a thin film layer made of silicon oxide.

Crystal plates 1 and 1c each having a mirror surface of 1 cm square and 50 μm on both sides and sputtered with 2000 Å of silicon oxide.
Quartz substrate 2 with both sides mirror-polished up to 500 μm square
Are bonded by a direct bonding technique through a silicon oxide film while maintaining the flatness, parallelism, and surface roughness required for the crystal device and direct bonding (FIG. 7B). Direct bonding
The crystal and the silicon oxide film are directly bonded together without using an adhesive. After the contact surface between the quartz plate and the silicon oxide film is sufficiently cleaned, a hydrophilizing treatment is performed with a mixed solution of hydrogen peroxide solution, ammonia and pure water to bring them into contact with each other by the intermolecular force of water molecules.
After that, when heat treatment is performed from 100 ° C. to 500 ° C., water molecules escape, and sufficient strength is obtained for bonding and polishing by intermolecular force. After that, both sides are polished together with the quartz substrate 2 until the quartz plate 1 becomes 15 μm (FIG. 7 (c)),
A quartz substrate 4 having a through hole is directly joined to the non-joining surface of the quartz plate 1 (FIG. 7D), silicon oxide is lifted off by buffered hydrofluoric acid to separate the quartz substrate 2, and chromium is used as an exciting electrode 3. 800Å and 3000Å gold was vapor deposited (Fig. 7
(E)).

In this embodiment, the vibrating crystal plate and the first substrate are directly bonded via the thin film layer. However, since the thin film layer can control the thickness and smoothness of the vibrating crystal plate accurately, It may be considered that the first substrate was directly bonded without the interposition of a thin film layer.
Since a thick carrier can be used, the vibrating crystal plate can be polished to 15 μm or less while maintaining the flatness, parallelism, and surface roughness required for the crystal device. With a conventional mass-produced crystal unit, the vibration frequency is 55 MH
Although z is the limit, the vibration frequency is 1 according to the present embodiment.
It was possible to obtain over 00 MHz.

Further, the first substrate material and the second substrate material can be separated even if the first substrate material and the second substrate material are the same material by directly bonding through the thin film layer, and a quartz substrate can be used as the first substrate. is there. (Embodiment 7) FIG. 8 is a diagram showing Embodiment 7 of the invention.
In the figure, 1 is a quartz plate for vibration, 2 is a first substrate made of a glass plate, 3 is an excitation electrode, 4 is a second substrate made of a silicon plate, 5 is a thin film layer made of silicon, 6 is an extraction electrode, 8 Is a groove.

Quartz crystal plate 1 with both sides mirror-polished up to 50 μm at 1 cm square and glass substrate 2 with 2000 Å silicon sputtered on both sides up to 500 μm at 1 cm square.
Are bonded by a direct bonding technique via silicon while maintaining the flatness, parallelism and surface roughness required for the crystal device and direct bonding (FIG. 8B). Direct bonding is a direct bonding of a crystal and a silicon film without using an adhesive. After the contact surface between the quartz plate and the silicon film is sufficiently cleaned, a hydrophilizing treatment is performed with a mixed solution of hydrogen peroxide solution, ammonia and pure water, and contact is made by the intermolecular force of water molecules. Then 100
When heat treatment is performed at a temperature of from 600 ° C. to 600 ° C., water molecules escape, and sufficient strength is obtained for bonding and polishing due to intermolecular force. After that, both sides are polished together with the glass substrate 2 until the crystal plate 1 becomes 15 μm (FIG. 8 (c)).
A silicon substrate 4 having a groove with a depth of 3000 Å and an embedded excitation electrode 3 of chromium and gold is directly bonded to the non-bonded surface of the substrate (Fig. 8 (d)), and silicon is lifted off by hydrazine to separate the glass substrate 2. Then, chromium (800Å) and gold (3000Å) were vapor-deposited on the vibrating crystal plate as the excitation electrodes (Fig. 8).
(E)).

In the conventional mass-producible crystal oscillator, the vibration frequency was limited to 55 MHz, but it was possible to obtain a vibration frequency of 100 MHz or more according to this embodiment. (Embodiment 8) FIG. 9 is a diagram showing Embodiment 8 of the present invention.
In the figure, 1 is a quartz plate for vibration, 2 is a first substrate made of silicon, 3 is an excitation electrode, 4 is a second substrate made of glass, 5
Is a thin film layer made of silicon oxide.

A vibrating quartz plate 1 which is mirror-polished on both sides up to 1 μm and 50 μm and sputtered with 3000 Å of silicon oxide.
With 1 cm square, both sides are polished to a mirror surface up to 1 mm and 3000 Å
The silicon substrate 2 sputtered with silicon oxide is bonded by a direct bonding technique via silicon oxide while maintaining the flatness, parallelism, and surface roughness required for the crystal device and direct bonding (see FIG. 9 ( b)). Direct bonding is a direct bonding of a silicon oxide film and a silicon oxide film without using an adhesive. After the contact surface between the silicon oxide film and the silicon oxide film is sufficiently cleaned, the surface is hydrophilized with a mixed solution of hydrogen peroxide solution, ammonia, and pure water to bring them into contact with each other by the intermolecular force of water molecules. After that, when heat treatment is performed from 100 ° C. to 500 ° C., water molecules escape, and sufficient strength is obtained for bonding and polishing by intermolecular force. Then, both sides are polished together with the silicon substrate 2 until the crystal plate 1 becomes 15 μm (FIG. 9 (c)),
A glass substrate 4 having a through hole is directly bonded to the non-bonded surface of the crystal plate 1 (FIG. 9 (d)), silicon oxide is lifted off by buffered hydrofluoric acid to separate the silicon substrate 2, and chromium is used as an excitation electrode at 800Å. , Gold was deposited by 3000Å (FIG. 9 (e)).

In the conventional mass-producible crystal oscillator, the vibration frequency was limited to 55 MHz, but it was possible to obtain a vibration frequency of 100 MHz or more according to this embodiment. (Ninth Embodiment) FIG. 10 is a diagram showing a ninth embodiment of the present invention. In the figure, 1 is a quartz plate for vibration, 2 is a first substrate made of a quartz plate, 3 is an excitation electrode, 4 is a second substrate made of a quartz plate,
Reference numeral 5 is a thin film layer made of silicon nitride, 6 is an extraction electrode, and 8 is a groove.

The quartz plate 1 having both sides mirror-polished up to 50 μm at 1 cm square and the first substrate 2 having both sides mirror-polished up to 500 μm at 1 cm square and sputtered with 2000 Å of silicon nitride are necessary for a crystal device and direct bonding. They are bonded by a direct bonding technique via silicon nitride while maintaining the flatness, parallelism, and surface roughness (FIG. 10B). Direct bonding
The crystal and the silicon nitride film are directly bonded together without using an adhesive. After the contact surface between the crystal plate and the silicon nitride film is sufficiently cleaned, a hydrophilizing treatment is performed with a mixed solution of hydrogen peroxide solution, ammonia and pure water to bring them into contact with each other by the intermolecular force of water molecules.
After that, when heat treatment is performed from 100 ° C. to 500 ° C., water molecules escape, and sufficient strength is obtained for bonding and polishing by intermolecular force. After that, double-side polishing is performed until the crystal plate 1 becomes 15 μm (FIG. 10 (c)), and a crystal substrate having a 3,000 Å deep groove on the non-bonded surface of the crystal plate 1 and burying the chromium and gold excitation electrodes. 4 are directly joined (see FIG. 10).
(D)), silicon nitride was lifted off with hydrofluoric acid to separate the quartz substrate 2, and 800 Å of chromium and 3000 Å of gold were vapor-deposited on the vibrating quartz plate as the excitation electrode 3 (Fig. 10 (e)).

In the conventional mass-producible crystal oscillator, the vibration frequency was limited to 55 MHz, but it was possible to obtain a vibration frequency of 100 MHz or more according to this embodiment. Further, in this embodiment, since the vibrating crystal plates are directly bonded to both surfaces of the substrate and both surfaces are polished, the yield is improved.

In each of Examples 3 to 6, the substrate is quartz, glass, silicon, quartz, the second substrate is quartz, silicon, glass, quartz, and the thin film layer is silicon oxide.
Although silicon, silicon oxide, and silicon nitride were used, the substrate was quartz, glass, and silicon, and the second substrate was quartz, glass,
The same effect can be obtained when any of silicon, silicon oxide, silicon nitride and silicon is used as the thin film layer. Further, even when the thin film layer is formed on the vibrating crystal plate, the first substrate, or both, the vibrating crystal plate and the substrate can be directly bonded, and the same effect can be obtained.

Further, even if the vibrating crystal plate is directly bonded to one surface of the first substrate or both surfaces are directly bonded, the thickness of the bonded portion is zero and polishing can be performed with a thick carrier.
It can be polished to m or less and a vibration frequency of 100 MHz or more can be obtained.

[0036]

As is apparent from the above description of the embodiments, the present invention uses a thick carrier by directly bonding a vibrating crystal plate to a non-deflecting substrate and simultaneously polishing the non-bonded surfaces on both sides. Since the bonding thickness is zero, it is possible to polish the vibrating crystal plate to 15 μm or less while maintaining the flatness, parallelism, and surface roughness required for the crystal device. The crystal unit it has can be mass-produced and can be produced with a high yield.

[Brief description of drawings]

1A is a perspective view of a vibrating quartz plate and a substrate before direct bonding in Example 1 of the present invention, FIG. 1B is a side view of a composite plate before polishing, and FIG. 1C is a composite after polishing. Side view of the plate (d) is a cross-sectional view of the crystal unit

FIG. 2 is a characteristic diagram of the crystal unit according to the first embodiment.

3A is a perspective view of a vibrating quartz plate and a substrate before direct bonding in Example 2 of the present invention, FIG. 3B is a side view of the composite plate before polishing, and FIG. 3C is a composite view after polishing. Side view of the plate (d) is a cross-sectional view of the crystal unit

4A is a perspective view of a vibrating quartz plate and a substrate before direct bonding in Example 3 of the present invention, FIG. 4B is a side view of the composite plate before polishing, and FIG. 4C is a composite view after polishing. Side view of the plate (d) is a cross-sectional view showing transfer of the crystal plate for vibration to the second substrate (e) is a cross-sectional view of the crystal resonator

5A is a perspective view of a vibrating crystal plate and a substrate before direct bonding in Example 4 of the present invention, FIG. 5B is a side view of a composite plate before polishing, and FIG. 5C is a composite view after polishing. Side view of the plate (d) is a cross-sectional view showing transfer of the crystal plate for vibration to the second substrate (e) is a cross-sectional view of the crystal resonator

6A is a perspective view of a vibrating quartz plate and a substrate before direct bonding in Example 5 of the present invention, FIG. 6B is a side view of the composite plate before the polishing, and FIG. 6C is a composite view after the polishing. Side view of the plate (d) is a cross-sectional view showing transfer of the crystal plate for vibration to the second substrate (e) is a cross-sectional view of the crystal resonator

7 (a) is a perspective view of a vibrating crystal plate and a substrate having a thin film layer formed on one surface before direct bonding in Example 6 of the present invention, and FIG. 7 (b) is a side view of the composite plate before polishing (c). ) Is a side view of the composite plate after the polishing. (D) is a cross-sectional view showing transfer of the vibration crystal plate to the second substrate. (E) is a cross-sectional view of the crystal oscillator.

FIG. 8A is a perspective view of a vibrating quartz plate before direct bonding and a substrate having a thin film layer formed on one surface thereof in Embodiment 7 of the present invention. FIG. 8B is a side view of the composite plate before polishing. ) Is a side view of the composite plate after the polishing. (D) is a cross-sectional view showing transfer of the vibration crystal plate to the second substrate. (E) is a cross-sectional view of the crystal oscillator.

9 (a) is a perspective view of a vibrating quartz plate having a thin film layer formed on one surface and a substrate having a thin film layer formed on one surface before direct bonding in Example 8 of the present invention. FIG. Side view of the composite plate (c) is a side view of the composite plate after the polishing (d) is a cross-sectional view showing transfer of the crystal plate for vibration to the second substrate (e) is a cross-sectional view of the crystal oscillator

10 (a) is a perspective view of a vibrating quartz plate before direct bonding and a substrate having thin film layers formed on both sides in Example 9 of the present invention. FIG. 10 (b) is a side view of the composite plate before polishing (c). ) Is a side view of the composite plate after the polishing. (D) is a cross-sectional view showing transfer of the vibration crystal plate to the second substrate. (E) is a cross-sectional view of the crystal oscillator.

FIG. 11 is a perspective view of a conventional crystal unit.

12A is a perspective view of a vibrating crystal plate and a reinforcing plate in a conventional example, FIG. 12B is a side view of the composite plate before the polishing, and FIG. 12C is a side view of the composite plate after the polishing. ) Is a cross-sectional view of the crystal unit

[Explanation of symbols]

 1 Vibration Quartz Plate 2 Substrate 3 Excitation Electrode 4 Second Substrate 5 Thin Film Layer 6 Extraction Electrode 7 Reinforcement Plate 8 Groove 9 Bump

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yutaka Taguchi, 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Inventor, Kazuo Eda, 1006 Kadoma, Kadoma City, Osaka

Claims (9)

[Claims] 1. A vibrating quartz plate is directly bonded onto a substrate, both non-bonded surfaces are simultaneously polished, and then a through hole is provided in the substrate so that a portion corresponding to the through hole is excited. A method for manufacturing a crystal unit, comprising forming electrodes. 2. The method for manufacturing a crystal unit according to claim 1, wherein glass or silicon is used as the substrate. 3. A vibrating crystal plate is directly bonded to one surface or both surfaces of a first substrate, both non-bonded surfaces are simultaneously polished on both surfaces, and the vibrating crystal is then mounted on a second substrate having through holes or grooves. A method for manufacturing a crystal resonator, comprising the steps of transferring a plate by direct bonding and forming electrodes so as to excite portions corresponding to the through holes or grooves. 4. The method of manufacturing a crystal resonator according to claim 3, wherein glass and silicon are used as the first substrate. 5. The method of manufacturing a crystal resonator according to claim 3, wherein crystal, glass, or silicon is used as the second substrate. 6. A thin film layer is formed on a first substrate, a vibrating crystal plate, or both, and the vibrating crystal plate is directly bonded to one surface or both surfaces of the first substrate via the thin film layer, and thereafter. After simultaneously polishing both non-bonded surfaces of the first substrate and the vibrating crystal plate, the vibrating crystal plate is directly bonded and transferred onto the second substrate having a through hole or a groove. A method of manufacturing a crystal resonator, comprising forming electrodes so as to excite portions corresponding to holes or grooves. 7. The method of manufacturing a crystal resonator according to claim 6, wherein crystal, glass, or silicon is used as the first substrate. 8. The method for manufacturing a crystal resonator according to claim 6, wherein crystal, glass, or silicon is used as the second substrate. 9. The method of manufacturing a crystal resonator according to claim 6, wherein silicon oxide, silicon nitride, or silicon is used as the thin film layer.