JP2001291948A - Mounting method for chip element and crystal oscillator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mounting method for chip element, with which short- circuiting caused by a conductive adhesive is prevented, and to provide a crystal oscillator for improving productivity which uses this method. SOLUTION: Concerning the mounting method for chip element for connecting a chip element, which has packaging terminals on both terminal sides, to each of terminal electrodes of a substrate by the conductive adhesive, an insulated adhesive is provided between the packaging terminals. Also, a groove having a protruding part on the center is provided between the terminal electrodes of the substrate, and the insulated adhesive is provide on the surface of the protruding part. Furthermore, the chip elements are capacitors, and the crystal oscillator is constituted by applying the mounting method therefor.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of mounting a chip element on a substrate in the industrial technical field, and more particularly to a mounting method used for a crystal oscillator.

[0002]

BACKGROUND OF THE INVENTION Crystal oscillators are widely used in electronic equipment, including communication equipment, as frequency and time reference sources. In recent years, miniaturization has become widespread as typified by portable types, and chip elements for this purpose have been further reduced in size, causing difficulty in mounting methods.

FIG. 3 is a cross-sectional view of a crystal oscillator illustrating a conventional example. The crystal oscillator includes a crystal body 2, an IC chip 3, and a capacitor 4 housed in a container body 1 having a concave portion and a step portion, and an opening surface is sealed with a cover 5. The IC chip 3 is fixed to the center of the bottom of the concave portion by face-down bonding.

The capacitors 4 are located on both sides of the IC chip 3, and mounting terminals 6 (ab) provided on both ends are fixed to terminal electrodes 7 (ab) on the bottom surface of the concave portion by a conductive adhesive 8. The crystal blank 2 is configured such that both ends of an extension electrode extending from an excitation electrode (not shown) are fixed to a step.

[0005]

[Problems to be Solved by the Invention]
However, the crystal oscillator having the above configuration has the following problem due to the downsizing of the capacitor 4 accompanying the downsizing. That is, due to the reduction in size, the distance between the mounting terminals 6 (ab) provided at both ends of the capacitor 4 becomes narrow, and it is difficult to control the amount of the conductive adhesive 8 applied. Had a short circuit problem. From this,
As the miniaturization progresses, there has been a problem that the productivity of the crystal oscillator is reduced.

(Object of the Invention) It is an object of the present invention to provide a method of mounting a chip element in which a short circuit due to a conductive adhesive is prevented and a crystal oscillator using the chip element to improve productivity.

[0007]

The basic solution of the present invention is to provide an insulating adhesive 9 between mounting terminals 6 (ab) provided at both ends of a chip element.

[0008]

In the present invention, since the insulating adhesive 9 is provided between the mounting terminals 6 (ab), the conductive adhesive 8 applied to both ends is divided. Hereinafter, an embodiment of the present invention will be described using a crystal oscillator as an example.

[0009]

FIG. 1 is a view of a crystal oscillator for explaining an embodiment of the present invention, in particular, a sectional view of mounting a capacitor. The same parts as those in the prior art are denoted by the same reference numerals, and description thereof will be simplified or omitted. As described above, in the crystal oscillator, the IC chip 3 and the capacitor 4 are fixed to the concave bottom surface of the IC chip 3 and the capacitor 4, the crystal piece 2 is held at the step of the container body, and the opening surface is sealed with a cover. (Fig. 1).

In this embodiment, a conductive adhesive 8 is applied to the terminal electrodes 7 (ab) provided on the bottom surface of the concave portion, and an insulating adhesive 9 is applied between the terminal electrodes 7 (ab). These are all thermosetting types. And the conductive adhesive 8
And the insulating adhesive 9 is cured, and the mounting terminals 6 (ab) on both ends of the capacitor 4 are connected to the terminal electrodes 7 (ab) on the bottom of the concave portion.
Connect to

With such a configuration, the insulating adhesive 9 is applied to the mounting terminal 6 (ab) of the capacitor 4 to prevent the conductive adhesive 8 from entering from both sides and cut off. Therefore, an electrical short circuit due to the conductive adhesive 8 can be prevented. Thereby, the productivity of the crystal oscillator can be increased.

[0012]

[Other matters] In the above embodiment, the bottom surface of the concave portion is flat.
For example, a groove 11 (ab) having a protrusion 10 at the center is provided between the terminal electrodes 7 (ab) on the bottom surface of the concave portion. Then, an insulating adhesive 9 may be provided on the surface of the protrusion 10. In this case, since the surplus of the conductive adhesive 8 flows into the groove 11 (ab), an electric short circuit is further prevented.

Also, the insulating adhesive 9 is applied to the mounting terminals 6 in advance.
The conductive adhesive 8 may be applied between (ab) and the conductive adhesive 8 as long as it can be divided. Although the crystal oscillator has been described as an example, the invention can be applied to a case where a chip element provided with mounting terminals 6 (ab) on both ends is mounted on a substrate.

[0014]

According to the present invention, the insulating adhesive 9 is provided between the mounting terminals provided on both ends of the chip element. A crystal oscillator that improves the productivity used can be provided.

[Brief description of the drawings]

FIG. 1 is a view of a crystal oscillator for explaining an embodiment of the present invention, particularly a sectional view of mounting a capacitor.

FIG. 2 is a view of a crystal oscillator for explaining another embodiment of the present invention, particularly a sectional view of mounting a capacitor.

FIG. 3 is a cross-sectional view of a crystal oscillator illustrating a conventional example.

FIG. 4 is a view of a crystal oscillator for explaining a conventional example, particularly a sectional view of mounting a capacitor.

[Description of Signs] 1 container body, 2 crystal pieces, 3 IC chips, 4 capacitors, 5 covers, 6 mounting terminals, 7 terminal electrodes, 8
Conductive adhesive, 9 insulating adhesive, 10 protrusion, 1
1 groove.

Claims (3)

[Claims] 1. A method of mounting a chip element, wherein a chip element having mounting terminals on both ends is connected to a terminal electrode of a substrate by a conductive adhesive, wherein an insulating adhesive is provided between the mounting terminals. The mounting method of the chip element. 2. A method of mounting a chip element, comprising: forming a groove having a projection in the center between terminal electrodes of the substrate; and providing an insulating adhesive on a surface of the projection. 3. The crystal oscillator according to claim 1, wherein said chip element is a capacitor.