JPH07283683A - Piezoelectric oscillator, piezoelectric vibrator, and piezoelectric oscillator - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a piezoelectric vibrator that has good drop characteristics even if the adhesion strength between the piezoelectric oscillator and the electrode is weak. Facilitates electrode formation without requiring a special technique for increasing the adhesion strength of the electrodes. [Structure] In the electrode of the piezoelectric oscillation piece, the fixed part is divided into a fixed part electrode and a fixed part, and the ratio of the fixed part electrode to the fixed part area is 1/3 or less, and the fixed part is fixed with a conductive adhesive. To fix. A piezoelectric oscillator using this piezoelectric oscillator and a piezoelectric oscillator composed of this piezoelectric oscillator.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a piezoelectric oscillator, a piezoelectric vibrator using the same, and an oscillator.

[0002]

2. Description of the Related Art A conventional piezoelectric oscillator will be described with reference to the top view of FIG.

FIG. 6 shows a piezoelectric oscillation piece of an electrode for supporting both ends. The metal electrodes 32 are formed on the front and back surfaces of the piezoelectric oscillation piece 31 by means such as vapor deposition and sputtering. Fixed part electrode 33
Was supported on both sides, so it was formed on the left and right in the longitudinal direction.

FIG. 7 shows a piezoelectric oscillation piece of an electrode for cantilever support. The metal electrodes 35 are formed on the front and back surfaces of the piezoelectric oscillation piece 34 by means such as vapor deposition and sputtering. Fixed part electrode 36
For cantilever support, it was formed by being divided into one end in the longitudinal direction. The electrode material is a single layer of Au, Ag, Ni, etc., and ion bombardment or ion platey leg technology is used to strengthen the adhesion between the piezoelectric oscillation pieces 31, 34 and the electrodes 32, 35 during vapor deposition. The metal particles during vapor deposition were accelerated and adhered to the piezoelectric oscillation pieces 31 and 34.

FIG. 8 shows a sectional view of a conventional piezoelectric vibrator.
The piezoelectric oscillation piece 38 in which the electrode 39 is formed on the base 37 such as ceramic is fixed by cantilever support with the conductive adhesive 40. After that, the frequency was adjusted, and the lid 41 was covered to seal the piezoelectric vibrator 42. In the case of using an oscillator, an IC was placed inside and sealed.

[0006]

However, in the conventional technique, the adhesion strength between the electrode and the piezoelectric oscillation piece tends to vary. Therefore, when the electrode and the piezoelectric oscillation piece are dropped by being incorporated in the piezoelectric vibrator or oscillator, the electrode and the piezoelectric oscillation piece are not easily dispersed. Peeling occurred between them, and the piezoelectric oscillation piece was removed from the base, resulting in a defect. Further, although ion bombardment or ion plating technology is used to increase the adhesion strength between the electrode and the piezoelectric oscillation piece during vapor deposition, there is a problem that it is difficult to set conditions and work is difficult.

[0007]

Therefore, the present invention solves such a drawback. In the electrode of the piezoelectric oscillation piece, the ratio of the area occupied by the electrode to the fixed portion is 1/3, and the rest is the base of the piezoelectric oscillation piece.

2. It is characterized in that the material of the electrode is formed of a single layer of metal such as Au, Ag and Ni.

3. In the cantilever-supported piezoelectric oscillation electrode, a boundary is formed by the electrodes in the adjacent portions of the electrodes divided into the left and right of the fixed portion.

4. It is characterized by conducting the front and back from the side.

5. Fix the piezoelectric oscillation piece with a conductive adhesive,
It is characterized by being sealed and used as a piezoelectric vibrator.

6. The oscillator is configured by combining and encapsulating a piezoelectric vibrator and an IC.

[0013]

[Embodiment] A piezoelectric oscillator according to the present invention will be described with reference to the top view of FIG.

FIG. 1 shows a piezoelectric oscillation piece of an electrode for supporting both ends. The electrode 2 is formed on the surface of the piezoelectric oscillating piece 1 by one layer of metal such as Au, Ag, Ni by using a method such as vapor deposition or sputtering.
The fixed part electrode 3 is formed on the left and right in the longitudinal direction for supporting both ends, and the part of the fixed part 4 that is the base of the piezoelectric oscillation piece 1 is formed ahead of it. When fixed, the area where the fixed portion 4 and the fixed portion electrode 3 are added becomes the area of the fixed portion, and the ratio of the fixed portion electrode 3 is set to 1/3 or less of the fixed portion area.

FIG. 2 is an inclined view of a piezoelectric oscillation piece of an electrode for cantilever support of the present invention. The metal electrodes 6 are formed on the front and back of the piezoelectric oscillation piece 5 by means such as vapor deposition and sputtering. Since the fixed part electrodes 7 are cantilevered, they are formed on the left and right in the short side direction,
The fixed portion 8 is formed at one end in the longitudinal direction with a portion of the piezoelectric oscillation piece 5 which remains as a base. Fixed part 8 when fixed
The area to which the fixed portion electrode 7 is added becomes the area of the fixed portion, but since it is cantilevered, it is divided at the center. The ratio of the fixed part electrode 7 to the area of the fixed part divided into the left and right is set to 1/3 or less.

FIG. 3 shows a sectional view of the piezoelectric vibrator of the present invention. The piezoelectric oscillation piece 5 with the electrode 6 formed on the base 9 is fixed by cantilever support. Fixed part 8 and fixed part electrode 7 on the fixed part
, And support the piezoelectric oscillation piece 5 with the conductive adhesive 10 etc. After that, the frequency is adjusted, and the lid 11 is covered in N ₂ or vacuum to seal the piezoelectric vibrator 12.
And Since the fixed part electrode 7 is for conducting the electrode 6 and the conductive adhesive 10, it has only to have a minimum area.

The same applies to the fixed part electrodes 3 on both ends of FIG.
If the adhesive force is maintained with the conductive adhesive 10 or the like at ⅔ or more of the area of the fixed portion, peeling does not occur.

FIG. 4 is a perspective view of a piezoelectric oscillator according to another embodiment of the present invention. Piezoelectric Piezoelectric oscillation piece 13 is formed with metal electrodes 14 on the front and back. Since the fixed electrode 15 is cantilevered,
It is formed on the left and right in the short side direction and divided at the center. The fixed portion 16 is formed at one end in the longitudinal direction as the base of the piezoelectric oscillation piece 13. The ratio of the fixed part electrode 15 to the area of the fixed part divided into the left and right is set to 1/3 or less. 2 /
If it is 3 or more, the adhesive force is maintained by the conductive adhesive 10 or the like to prevent peeling.

In the case of fixing by cantilever support, the electrode shape of the piezoelectric oscillation piece 5 of FIG. 2 may be used, but if the conductive adhesive 10 is applied and fixed on the left and right sides of the short side direction, it depends on the type of the conductive adhesive 10. The solvent inside may exude and become a short circuit.

The electrode shape of the piezoelectric oscillating piece 13 in FIG. 4 is an improvement of these, and since the boundary between the fixed portion electrodes 15 is formed by the electrodes at the left and right adjacent portions in the short side direction, a conductive adhesive is used. It was devised to prevent the solvent 10 from seeping out like waste.

The fixed portion of the piezoelectric oscillation piece 13 of FIG. 4 is a portion obtained by adding the fixed portion electrode 15 and the fixed portion 16 excluding the portion divided at the center, and of the area of the fixed portion, the fixed portion electrode 15 has a fixed portion. The ratio is 1/3 or less. If it is ⅔ or more, the adhesive force is maintained by the conductive adhesive 10 or the like to prevent peeling.

In the piezoelectric oscillating piece 1 of FIG. 1, the piezoelectric oscillating piece 5 of FIG. 2, and the piezoelectric oscillating piece 13 of FIG. This is formed by extending the fixed part electrodes 3, 7, and 15, respectively. It can be easily formed by performing oblique vapor deposition during vapor deposition.

FIG. 5 shows a sectional view of another embodiment of the piezoelectric vibrator of the present invention. The IC chip 18 is fixed to the base 17 with the conductive adhesive 10, and wire bonding is performed with the AU wire 19 or the like. Metal electrodes 21 are formed on the front and back of the piezoelectric oscillation piece 20, a fixed portion 23 and a fixed portion electrode 22 are placed on a fixed portion, and a conductive adhesive 10 is used to support the base 17 in a cantilevered manner.
Fixed to. After that, the frequency is adjusted, and the lid 24 is covered in N ₂ or in vacuum to seal the piezoelectric oscillator 25.

[0024]

According to the present invention, the adhesion strength of the electrodes of the piezoelectric oscillation piece is controlled by setting the ratio of the fixed portion electrode of the fixed portion of the piezoelectric oscillation piece and the fixed portion electrode of the fixed portion to 1/3 or less of the area of the fixed portion. Even if the pressure is weak, two-thirds or more of the base of the piezoelectric oscillation piece is fixed with a conductive adhesive, so that drop defects due to electrode peeling are eliminated and impact resistance is improved.

Further, since the adhesion strength of the electrodes may be weak, no special technique for increasing the adhesion strength such as ion bombardment or ion plating is required, which facilitates the manufacture. Since the adhesion strength of the electrodes is weak, the strain on the piezoelectric oscillation piece is reduced, so that the aging characteristic showing the frequency change for a long time is improved.

[Brief description of drawings]

FIG. 1 is a top view of a piezoelectric oscillation piece for supporting both ends of the present invention.

FIG. 2 is a perspective view of a cantilever-supporting piezoelectric oscillation piece of the present invention.

FIG. 3 is a sectional view of the piezoelectric vibrator of the present invention.

FIG. 4 is a perspective view of a piezoelectric oscillator according to another embodiment of the present invention.

FIG. 5 is a sectional view of another embodiment of the piezoelectric vibrator of the present invention.

FIG. 6 is a top view of a conventional piezoelectric oscillation piece for supporting both ends.

FIG. 7 is a perspective view of a conventional cantilever-supporting piezoelectric oscillation piece.

FIG. 8 is a sectional view of a conventional piezoelectric vibrator.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Piezoelectric oscillation piece 2 ... Electrode 3 ... Fixed part electrode 4 ... Fixed part 5 ... Piezoelectric oscillation piece 6 ... Electrode 7 ... Fixed part electrode 8 ... Fixed part 9 ... Base 10 ... Conductive adhesive 11 ... Lid 12 ... Piezoelectric vibrator 13 ... Piezoelectric oscillator 14 ... Electrode 15 ... Fixed part electrode 16 ... Fixed part 17 ... Base 18 ... IC 19-Au wire 20-Piezoelectric oscillation piece 21-Electrode 22-Fixing electrode 23-Fixing part 24-Lid 25-Piezoelectric oscillator 31-Piezoelectric oscillation piece 32-Electrode 33-Fixing Part electrode 34..Piezoelectric oscillation piece 35..Electrode 36..Fixed part electrode 37..Base 38..Piezoelectric oscillation piece 39..Electrode 40..Conductive adhesive 41..Lid 42..Piezoelectric vibrator

Claims (6)

[Claims] 1. A piezoelectric oscillating piece, wherein the electrode occupies 1/3 or less of the area of the fixed portion of the electrode of the piezoelectric oscillating piece, and the rest remains the base of the piezoelectric oscillating piece. 2. The piezoelectric oscillating piece according to claim 1, wherein the material of the electrode is a single layer of metal such as Au, Ag or Ni. 3. The piezoelectric oscillation according to claim 1, wherein in the electrode of the cantilever-supported piezoelectric oscillation piece, a boundary is formed by the electrode in a portion adjacent to the left and right divided electrodes of the fixed portion. One piece. 4. The piezoelectric oscillating piece according to claim 1, wherein the front and back are electrically connected by side surfaces. 5. A piezoelectric vibrator, wherein the piezoelectric oscillation piece according to claim 1, claim 2, claim 3 or claim 4 is fixed and sealed with a conductive adhesive. 6. A piezoelectric oscillator, wherein an oscillator is formed by combining and sealing the piezoelectric vibrator according to claim 5 and an IC.