JPH03208408A - Chip type surface acoustic wave device - Google Patents

Abstract

PURPOSE:To reduce the effect of a mechanical deformation applied to an alumina ceramic plate or a thermal stress onto a surface acoustic wave element by fixing the surface acoustic wave element at a part having a slot of the alumina ceramic plate with the slot formed therearound. CONSTITUTION:An electrode 4 is formed to an alumina ceramic plate 3 with a part 2 having a groove 1 formed therearound. A silicone resin is coated to the part 2 having the groove 1 is applied around the alumina ceramic plate 3, the surface acoustic wave element is adhered and cured thermally and connects to the electrode 4 by wire bonding. Since the coated silicone resin does not flow at the outside of the groove 1, the surface acoustic wave element and the alumina ceramic plate 3 are adhered only at the part 2 having the groove 1, the adhered area is made constant and the characteristic of the surface acoustic wave element is made stable.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a chip-type surface acoustic wave device that can be soldered with a lip opening and is used in television receivers, video tape recorders, and the like.

2. Description of the Related Art A conventional chip-type surface acoustic wave device will be described below. A chip-type surface acoustic wave device has a structure in which a surface acoustic wave element is fixed to a chip carrier made of an alumina porcelain plate, and after electrical connection is made, a space is maintained and sealed. 6, an electrode 6 is formed,
An elastic surface flow element (not shown) is entirely fixed to the alumina porcelain plate 6 with an adhesive, and connected to the electrode 6 by wire bonding.

Problems to be Solved by the Invention However, in the above-mentioned conventional configuration, the surface acoustic wave element and the alumina porcelain plate 6 are completely fixed with adhesive;
Mechanical deformation of the Aminina porcelain 6, such as a change in the center frequency of the surface acoustic wave device before and after the process of sealing with a cap, or an increase in the amount of drift of the center frequency due to temperature,
There has been a problem in that thermal strain directly affects the surface acoustic wave element and adversely affects the characteristics of the surface acoustic wave device.

The present invention solves the above-mentioned conventional problems, and aims to provide a chip-type surface acoustic wave device that reduces the influence of mechanical deformation of an alumina porcelain plate and thermal strain on a surface acoustic wave element. purpose.

Means for Solving the Problem In order to solve this problem, the chip-type surface acoustic wave device of the present invention includes forming a grooved portion around a receptacle for fixing a surface acoustic wave element to a part of an alumina porcelain plate. , the surface acoustic wave element is fixed to this portion using an adhesive.

Effect: With this configuration, the adhesive used for the adhesive part does not spread outside the adhesive part of the alumina porcelain plate, so the adhesive area of the surface acoustic wave element becomes constant, and the entire surface of the surface acoustic wave element is not adhered to the alumina porcelain plate. Mechanical deformation and thermal strain of the alumina porcelain plate no longer directly affect the surface acoustic wave element, and the effect on the characteristics of the surface acoustic wave device can be reduced.

EXAMPLE Hereinafter, an example of the present invention will be described with reference to the drawings.

As shown in FIGS. 1 and 2, an electrode 4 is formed on an alumina porcelain plate 3, which has a portion 2 having a groove 1 around its periphery. A silicone resin is applied to a portion 2 having a groove 1 around the alumina porcelain plate 3, and a surface acoustic wave element (not shown) is formed.
After bonding and thermosetting, it is connected to the electrode 4 by wire bonding.

As described above, according to this embodiment, the applied silicone resin does not flow out to the outside of the groove 1, so the surface acoustic wave element and the alumina porcelain plate 3 are bonded only at the portion 2 where the groove 1 is located. Therefore, the bonding area becomes constant, the characteristics of the surface acoustic wave device are stabilized, and the influence of mechanical deformation and thermal strain applied to the alumina porcelain plate 3 on the surface acoustic wave device can be reduced.

In one embodiment of the present invention, the shape of the portion 2 having the groove 1 around it is rectangular, but it goes without saying that it may be circular or other shapes.

Effects of the Invention As is clear from the above description of the embodiments, the present invention provides a part of an alumina porcelain plate with a grooved part around the holder for bonding a surface acoustic wave element, and only this part can be used to make an alumina porcelain plate. An excellent chip-type surface acoustic wave device in which the bonding area changes depending on the structure in which the plate and surface acoustic wave element are bonded, reducing the effects of mechanical deformation on the alumina porcelain plate and thermal strain on the surface acoustic wave element. It is possible to realize this.

[Brief explanation of drawings]

FIG. 1 is a perspective view of an alumina porcelain plate made of alumina porcelain according to an embodiment of the present invention. 1... Groove, 2... Part with groove around it,
3...Alumina porcelain plate.

Claims (1)

[Claims] A chip-type surface acoustic wave device in which a surface acoustic wave element is fixed only by the grooved portion of an alumina porcelain plate having a grooved portion formed around the periphery.