JPH029723B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a piezoelectric device, and particularly to a method for manufacturing a flat piezoelectric device using a piezoelectric device chip with its main plane fixed horizontally.

(Prior art) Piezoelectric devices such as crystal oscillators and filters, which have been used in various electronic devices such as communication devices, are
As shown in the figure, it has been common practice to firmly hold a piezoelectric device chip 1 at one end of leads 3, 3 which hermetically pass through a base 2, and to hermetically seal it with a sealing tube 4.

However, in recent years, as various electronic devices have become required to be smaller and thinner, conventional rigid piezoelectric devices such as those mentioned above are mounted on printed circuit boards at a much higher position than other electronic components. There was a serious defect in that not only did it significantly damage the space factor of the electronic equipment to be mounted, but it was also difficult to apply it to automatic mounting machines.

In order to solve this problem, a type of package in which a piezoelectric device chip 6 is horizontally sealed in a shallow dish-shaped package 5 as shown in FIG. 6 has been proposed. Part 7
It is difficult and complicated to determine the position when mounting the device, which makes it difficult to mass-produce and makes automation difficult.

In addition, a patent application was filed in 1983 for improved mass production.
89390, in which the vibrator is bonded to a flexible flat plate material called a hoop material, and positioning is ensured by bonding the hoop material to the leads. The vibrator coupled to the conductive elastic support must be separated from the material, which requires a large number of man-hours, and furthermore, the shape of the package and lead is difficult to automate and mass-produce.

(Objective of the Invention) The present invention has been made to eliminate the defects of the flat piezoelectric device as described above, and an object thereof is to provide a flat piezoelectric device that requires less man-hours and is highly automated and mass-producible.

(Summary of the Invention) To achieve this object, the piezoelectric device of the present invention is a piezoelectric device sealed in a flat airtight container having a lid bonded to the opening edge and a lead member hermetically passing through the side wall of the package. In the case where the lead member is composed of two members, an outer lead member whose main part is a part that penetrates the side wall of the package, and an inner lead member that supports and fixes the piezoelectric device chip, the outer lead a first step of bending the lead portion of the member inside the side wall of the airtight container and embedding the side of the bent portion of the lead member facing the inner wall in the wall to form a package having an external lead member; A second step of forming an internal lead member by standing up the chip fixing terminal part of the internal lead member whose main part is the device chip fixing base and bending the tip of the fixed terminal part, and fixing the internal lead member. A third step of mounting and fixing the piezoelectric device chip on the terminal part, and fitting the internal lead member with the piezoelectric device chip mounted and fixed into the package provided with the external lead member, and fixing the internal lead member. A fourth method for making each of the fixed terminal parts independent by joining the terminal part and the external lead member of the package and by resistively heating and fusing a bridge part provided on the internal lead member that joins the fixed terminal part to each other. A piezoelectric device is constructed by the steps.

(Example) Hereinafter, the present invention will be described in detail based on an example shown in the drawings.

First, prior to explaining the embodiments of the present invention, the defects of the conventional flat type package will be explained in some detail. Furthermore, since the above-mentioned Japanese Patent Application No. 1989-89390 does not contain any detailed description of the manufacturing process, it is noted that
This will be explained using figures.

The manufacturing process of the conventionally commonly used flat type package is as shown in Fig. 9a.
When forming the package, the lead member 10 is passed through and integrally formed, and the piezoelectric device is inserted into the package.
Place the chip 11.

Next, as shown in Figure b, the piezoelectric device chip 1
1 and the lead member 10 with a conductive adhesive or solder 12, etc., and further, the outer periphery of the lid 13 and the open end of the package 9 are joined in a vacuum or in an inert gas. This seals the inside of the package with vacuum or inert gas.

However, the conventional method as described above requires a large number of steps, and also requires two steps when joining the piezoelectric device to the lead part.
The piezoelectric device must be placed on the lead member of the book, and its positioning is difficult, resulting in poor yields and low mass production.In addition, the side walls of the package cannot be made sufficiently thick due to package size limitations, making it difficult to position the piezoelectric device. Since the member 10 linearly penetrates the side wall of the package, the airtightness of the penetrating portion is incomplete and the characteristics of the enclosed piezoelectric device deteriorate over time.

In order to eliminate such defects of the conventional flat type package, the present invention takes the following measures.

First, the first step is to bend the lead member 21 that has passed through the side wall of the package cage 20 inside the side wall as shown in FIGS. The outer frame body is configured to be embedded in the external lead member.

By doing this, it is possible to sufficiently increase the bonding distance and area between the lead member and the wall without increasing the thickness of the package wall, thereby securing the internal volume without increasing the package size, and increasing the lead thickness. It is possible to improve resistance to airtight failure due to stress applied to the member.

Incidentally, a conductive surface 22 connected to the lead member 21 and extending to the inner bottom of the package is an electromagnetic shield or a grounding plate.

A package with such a structure is made by putting a preform part made of insulating material such as glass into a mold and baking it together with a lead member and an opening flange member.・A large number of lead members 26, 26, . . . arranged on the frame 25 and flanges 28, 2 arranged on the similar lead frame 27
8.... can be easily carried out by manufacturing a large number of packages at once by precisely aligning the preform components such as glass with the above-mentioned preform parts using the mold placement alignment holes 29, and then baking and hardening them. be able to.

Next, the second step of forming internal leads will be explained.

This is done by forming a thin metal plate having spring properties, such as molybdenum, nickel, or phosphor bronze, into the shape shown in FIG. An inner lead member as shown in FIG. 3d is manufactured by bending the inner lead member inward.

Incidentally, the lead 32 of the internal lead 31 is a contact lead, which is used when, for example, conductive contact with the lid is required.

The internal leads 31 can also be manufactured all at once by arranging a large number of them on a lead frame 34 and photographing them as shown in FIG.

Further, the fixed base 31 includes an ultra-thin bridge portion 33 designed to provide a high electrical resistance value.
33, . . . are provided, which are used when separating each fixed terminal 30 after the internal lead 31 is installed in the package 20, as will be described later.

In the third step, the piezoelectric device chip is fixed onto the internal lead 31 formed as described above using an automated device, and the fixed terminal 30 and the piezoelectric device chip are fixed on the internal lead 31 formed as described above.
The chip 35 is bonded to the chip 35 using, for example, a conductive adhesive 36, and through this process, as shown in FIG.
A subassembly part 37 as shown in FIG.

The subassembly component 37 must be selected to have a size that allows it to be placed within the external lead member, and a size that allows the bottom of each fixed terminal 30 of the subassembly component to come into contact with the lead member 21 of the external lead member when placed. There is no need to tell you that.

Next, the fourth step will be explained.

The subassembly part 37 is placed in the flat external lead member described above, and the fixed terminal part 30 of the subassembly part 37 and the lead member 21 of the external lead member are connected and fixed by soldering or spot welding. Furthermore, by making each leg of the internal lead member electrically independent, it is possible to mass produce piezoelectric devices as shown in FIG. It may be manufactured by covering the lid 40 under the following conditions.

Since the present invention is constructed as described above, it is possible to ensure the airtightness of a flat type airtight container suitable for manufacturing a piezoelectric device that is small in size, low profile, and easy to chip, without sacrificing its external size and internal volume. It can be easily and reliably manufactured without any damage, and the component parts are divided to make it suitable for automation in the manufacturing process, making mass production easier. Therefore, it can be supplied at low cost, and there is no change in characteristics due to hermetic breakdown of the piezoelectric device. It has a significant effect on preventing problems, improving reliability, and reducing costs.

[Brief explanation of drawings]

1A and 1B are views showing the structure of a package using the manufacturing method according to the present invention, FIGS. 2A and 2B are views showing an example of forming a package using the manufacturing method according to the present invention, and FIG. FIG. 4 is a diagram showing the configuration and an embodiment of a piezoelectric device fixing stand using the manufacturing method according to the present invention, and FIG. 4 is a diagram showing an embodiment of the piezoelectric device manufactured using the manufacturing method according to the present invention. 5 and 6 are cross-sectional views showing the structure of a conventionally used piezoelectric device, and FIG. 7 is a diagram explaining the manufacturing process of a conventionally used piezoelectric device. 1, 6, 11, 35...Device chip, 2
... Base, 3, 32 ... Lead, 4 ... Sealed tube, 5, 9, 20 ... Package, 7, 10, 2
1, 26... Lead member, 8, 13, 40...
Lid, 12, 36... Solder, 22... Electromagnetic shield or ground plate, 25, 27, 34... Lead frame, 28... Flange, 29... Positioning hole, 30... Fixed terminal, 31... Fixed stand, 33...
...Bridge part, 37...Assembly parts.

Claims (1)

[Claims] 1 A piezoelectric device sealed in a flat type airtight container having a lid adhered to the edge of the opening and a lead member hermetically passing through the side wall of the package, the lead member having an external part whose main part is the part passing through the side wall of the package. In a device composed of two members: a lead member and an internal lead member that supports and fixes the piezoelectric device chip, the lead portion of the external lead member is bent inside the side wall of the airtight container, and the lead member A first step of embedding the side facing the inner wall of the bent part in the wall to form a package having an external lead member, and a chip fixing terminal portion of the inner lead member whose main part is a piezoelectric device/chip fixing base. A second member is made to stand upright and the tip of the fixed terminal portion is bent to form an internal lead member.
a third step of mounting and fixing a piezoelectric device chip on the fixed terminal portion of the internal lead member;
The internal lead member on which the piezoelectric device chip is mounted and fixed is fitted into the package provided with the external lead member, and the fixed terminal portion of the internal lead member and the external lead member of the package are joined, and the internal lead member manufacturing a piezoelectric device, characterized in that the piezoelectric device is constructed by a fourth step of making each of the fixed terminal parts independent by resistance-heating and melting a bridge part that connects the fixed terminal parts provided in the above to each other; Method.