JPH02179013A - Crystal resonator and its manufacture - Google Patents

Abstract

PURPOSE:To improve the stability of the frequency by storing a vibration piece whose rear and front sides are arranged with a main electrode in a retainer, evaporating a metallic coat film by a laser beam and depositing the evaporated metal onto the main electrode of the vibration piece so as to seal the vibration piece under a high vacuum thereby decreasing the equivalent resistance. CONSTITUTION:The vibration piece 4 whose rear and front sides are arranged with a main electrode 6 is supported to a lead terminal 3 of a retainer with a conductive adhesives 5 and in the electrical continuity state. Moreover, a metallic coat film is applied to a transparent glass cover 1 with the vapor deposition method, a small hole 9 is provided to a case 2, a low melting point glass 8 is applied between the case 2 and the cover 1 and the terminal 3 and the vibration piece 4 are stored in an N2 gas. Then the small hole 9 is sealed air-tightly under vacuum by using a low melting point bulk glass seal member 10. Then the terminal 3 is connected to an oscillator after vacuum sealing, the oscillated frequency is confirmed by a counter, and a YAG laser beam 21 being a pulsive continuous stimulated light is focused at the outside of the cover 1 and the metallic coat film is irradiated the laser beam 21.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a crystal resonator used in oscillation circuits of consumer equipment and a method for manufacturing the same.

BACKGROUND ART FIG. 3 is a structural diagram of a conventional general crystal resonator. In FIG. 3, a vibrating piece 2e with main electrodes 2T arranged on the front and back sides is supported by a holding part of a lead terminal 24 by a conductive adhesive 26 and is electrically connected to the lead terminal 24.
is led out to the outside of the cage 23 via the low melting point glass 29 section.

The retainer 23 was made of a metal cap, and was hermetically sealed by resistance welding to the paste 22.

Next, fine adjustment of the frequency of the conventional crystal oscillator is performed by depositing the secondary electrode 28 again on the main electrode 27 in a vacuum, which is sealed with the metal cap 23, and lowering the frequency by a predetermined amount. Ta.

Problems to be Solved by the Invention However, as mentioned above, in the conventional cage, the low melting point glass 2
9, but the sealing conditions are 430℃, 1
Due to the strict conditions of approximately 0 minutes, there was a problem in that the frequency drift before and after sealing became large.

Furthermore, since the vibrating element 26 is not affected by the atmosphere in a vacuum, the equivalent resistance is lowered and the frequency stability is improved. There was a problem in that high vacuum sealing could not be achieved due to the generation of bubbles, resulting in a decrease in single frequency stability.

Therefore, an object of the present invention is to improve frequency stability by making it possible to finely adjust the frequency after the crystal resonator is completely sealed in a high vacuum and hermetically sealed.

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention provides a method in which a small hole is provided in a holder having a cover that at least partially transmits laser light, and a metal coating film is arranged on the inside of the cover. 1. After storing the vibrating piece with main electrodes on the front and back sides in the holder, the small hole is hermetically sealed with a sealing material in a vacuum, and the metal coating film is evaporated with laser light to remove the main electrode of the vibrating piece. It is to be attached to.

According to the present invention, the vibrating element can be sealed in a high vacuum by the above-described structure and manufacturing method, and the equivalent resistance can be reduced and the frequency stability can be improved. Furthermore, it is possible to finely adjust the frequency even after hermetically sealing, and frequency deviation can be reduced.

Example FIG. 1 is a partially cut away perspective view showing one embodiment of the present invention.

It is a diagram. The vibrating piece 4, which has main electrodes 6 arranged on the front and back sides, is supported by the holding part of the lead terminal 3 by a conductive adhesive 6 and is electrically connected to the holding part of the lead terminal 3. A metal coating film 7 is disposed on the transparent glass cover 1 by a vapor deposition method. Further, a small hole 9 is provided in the case 2, and a low melting point glass 8 is applied between the case 2 and the cover 1, and the lead terminal 3 and the vibrating piece 4 are housed in N2. Next, the small hole 9 is hermetically sealed in a vacuum using a sealing material 1o made of low melting point bulk glass.

The sealing material 1o made of low melting point bulk glass does not generate bubbles even in a high vacuum and can be used as a sealing material for the small holes 9. In addition, by increasing the sealing temperature of the low melting point glass 8 used for sealing the glass cover 1 and the case 2 by about 60°C higher than the sealing material 1o made of low melting point bulk glass, the sealing material 1o has a low melting point during sealing. The glass 8 is prevented from melting.

With the above configuration, even when the small hole 9 is hermetically sealed with the sealing material 1o, high vacuum sealing is possible, the equivalent resistance of the vibrating element 4 can be reduced, and the frequency stability can be improved.

In one embodiment of the present invention, a sealing material 1o made of low melting point bulk glass was used to seal the small hole 9.

High melting point no-flux solder can also be used. Further, although the small hole 9 is provided in the case 2, it may be provided at any arbitrary location on the glass cover 1. Although the sealing method was performed by heating the entire portion, the small holes 9 may also be sealed by partial heating using a laser beam or a light beam.

FIG. 2 is a conceptual diagram of fine frequency adjustment using laser light after vacuum sealing. The lead terminal 3 is connected to an oscillator, and the oscillation frequency can be checked with a counter. Here, YAC laser light 21, which is a continuous wave light pulsed by a Q switch, is irradiated from the outside through the glass cover 1 with a focus near the metal coating film γ and outside the glass cover 1.

Most of the Y/G laser beam 21 (1.06 μm) passes through the glass cover 1 and can selectively evaporate only the metal coating film 7. Since the evaporated metal 19 adheres to the main electrode 6 disposed on the vibrating element 4, the oscillation frequency of the vibrating element 4 can be lowered. Furthermore, the frequency is finely adjusted by repeatedly sweeping the Y/G laser beam 21 until it reaches a predetermined set frequency.

Although a YAG laser beam was used in this embodiment, other laser beams can also be used as long as they can pass through the glass cover 1. Furthermore, although mug was used for the main electrode 6 and the metal coating film 7, other metals may also be used.

According to the above-mentioned frequency fine adjustment method, the crystal resonator itself can be placed in the atmosphere, so that continuous frequency fine adjustment is possible with simple equipment.

Furthermore, since the frequency is finely adjusted after hermetically sealing, the frequency deviation can be reduced, and the equivalent resistance is less likely to deteriorate.

Further, the frequency may be finely adjusted before the small hole 9 is sealed.

In this case as well, the metal coat film 7 previously deposited on the glass cover 1 is irradiated with the laser beam 21 through the glass cover 1 to evaporate the metal coat film 7 and attach it to the vibrating element 4.

Effects of the Invention As is clear from the above explanation, according to the crystal sensor and its manufacturing method of the present invention, the vibrating element can be sealed in a high vacuum, so the equivalent resistance can be reduced and the frequency stability can be improved. You can improve. Furthermore, it is possible to finely adjust the frequency even after hermetically sealing, and frequency deviation can be reduced. Furthermore, by using laser light, the adjustment range can be widened in the same way as in conventional vapor deposition methods, and there is no deterioration in unit equivalent resistance, making it possible to realize a production process that is extremely suitable for mass production.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway perspective view showing an embodiment of the present invention. FIG. 2 is a cross-sectional view showing the concept of finely adjusting the frequency using a laser beam after vacuum sealing. FIG. 3 is a partially cutaway front view of a conventional general crystal resonator. 1...Glass cover, 2.River...Case, 3.
...Lead terminal, 4...Vibration piece, 5...
...Conductive adhesive. e... Main electrode, 7... Metal coated film,
8...Low melting point glass, 9...Small hole, 1
0... Seal material, 20... Lens, 2
1. River... Racer light. /--One Karas Cover Figure 3

Claims (3)

[Claims] (1) A holder that has a cover that at least partially transmits laser light and has a vacuum inside, a sealing material that seals a small hole provided in the holder, and a metal provided inside the cover. A crystal resonator comprising a coating film and a vibrating piece having main electrodes on the front and back sides and housed in the holder. (2) A small hole is made in the holder, which has a cover that at least partially transmits the laser beam, and a metal coating film is arranged inside the cover, and a vibrating piece with main electrodes arranged on the front and back is bonded with a conductive adhesive. After being supported by a holding part and electrically connected and housed in the holder, the small hole is hermetically sealed with a sealing material in a vacuum, and then the metal coating film is evaporated with a laser beam in an atmospheric atmosphere. A method of manufacturing a crystal resonator in which the frequency is adjusted by attaching it to a vibrating piece. (3) A small hole is made in the holder, which has a cover that at least partially transmits laser light, and a metal coated film is arranged inside the cover, and a vibrating piece with main electrodes arranged on the front and back is bonded with conductive adhesive. After being supported by a holding part, electrically connected, and housed in the holder, the metal coating film is evaporated with a laser beam in a vacuum and attached to the vibrating element to adjust the frequency, and then a sealing material is used to adjust the frequency. A method for manufacturing a crystal resonator that hermetically seals small holes.