JP4615704B2 - Method for manufacturing piezoelectric vibrator - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for manufacturing a crystal resonator that mounts and holds a piezoelectric element plate obliquely with respect to a substrate.
[0002]
[Prior art]
With the recent high functionality, high precision, miniaturization, and weight reduction of electronic devices, similar problems have been demanded for electronic components mounted on these electronic devices. For example, even if it takes the container structure of an electronic component, instead of the conventional metal container, it is working on the improvement of the above-mentioned requirements by developing to one using a ceramic material. In relation to the container shape, the mounting of components has changed from the conventional lead shape to the terminal shape of semiconductor component packages (DIP, ZIP, QFP, etc.), and also to the surface mounting shape with electrodes metallized on the substrate surface. It has expanded.
[0003]
On the other hand, the holding structure of the vibration element plate housed in the piezoelectric component container is also changed from a support structure for metal pieces (metal support) to a support structure that is directly mounted on a substrate as the container outer shape becomes smaller. In the direct mounting on the substrate, a conductive adhesive, solder, or a flip chip method similar to a semiconductor integrated component is being introduced. As for the support of the vibration element plate, in order to satisfy the mechanical drop impact, the thermal expansion change between the vibration element plate and the substrate (mounting holding part) when holding both ends in the longitudinal direction of the vibration element plate In order to cope with this, a structure for holding one side (cantilever) of the vibration element plate in the longitudinal direction is also employed.
[0004]
[Problems to be solved by the invention]
However, as mentioned in the prior art, recently, piezoelectric parts have been rapidly changing to miniaturization, so the external dimensions of piezoelectric parts have become smaller and extremely small with changes in the shape and mounting structure of piezoelectric parts. Therefore, as the outer shape of the container shape becomes smaller, the vibration element plate stored in the container must be made smaller.
[0005]
However, even if the outer shape of the vibration element plate is reduced, in order to obtain various (from low to high frequency) oscillation frequencies, the vibration element plate needs to be thicker or thinner, and the piezoelectric container becomes smaller. In particular, it is difficult to secure a sufficient holding area to hold the vibration element plate, and there is a problem that it is difficult to sufficiently maintain the holding strength of the vibration element plate in the piezoelectric component container.
[0006]
[Means for Solving the Problems]
In order to solve the above-described problem, in a method of manufacturing a piezoelectric vibrator in which a vibration element plate is cantilevered using an adhesive on a substrate, the vibration element plate is mounted on the substrate and held by a conductive adhesive. And reversing the state in which the vibrating element plate is held on the substrate using an inverting jig before the conductive adhesive is cured, and holding the vibrating element plate obliquely with respect to the substrate. A method of manufacturing a piezoelectric vibrator including a step and a step of drying and curing the conductive adhesive in the inverted state, and the mounting position of the vibration element plate is for improving the adhesive strength of the conductive adhesive And a method of manufacturing a piezoelectric vibrator having a concave dent.
[0007]
Therefore, the vibration element plate is mounted and held with an inclination angle by the above-described method of manufacturing a piezoelectric vibrator, so that the vibration element can be compared with the case where a mechanical drop impact is applied by conventional cantilever holding. Adhesive strength can be satisfied because a sufficient adhesive paste can be supplied to the place holding the plate. In addition, as the piezoelectric container becomes smaller, it becomes difficult to secure a sufficient holding area to hold the vibration element plate. The adhesive strength of the vibration element plate is enhanced by forming a concave dent in the holding part of the piezoelectric element plate to which the conductive adhesive is applied at the place where the element plate is mounted.
[0008]
【background】
In JP-A-8-330886, a device piece is disposed on a surface of a flat base made of ceramics while being inclined, and the lower end of the device piece is fixed to a metallized wiring on the base via a conductive adhesive. There is a disclosure of the invention characterized by the above. However, in the above publication, there is a description of securing the inclination of the device piece by means of the device piece bonding method and the device such as reinforcement or V-shape at the bonding portion.
[0009]
As the present invention is rapidly changing to recent miniaturization of piezoelectric parts, the outer dimensions of the piezoelectric parts are miniaturized, the outer dimensions of the piezoelectric parts are miniaturized, and the outer dimensions of the piezoelectric parts are miniaturized, Disclosed is a manufacturing method in which a piezoelectric element plate is obliquely mounted and held in a container in order to improve the holding strength of the vibration element plate resulting from a decrease in the container internal volume (mounting area of the vibration element plate) Thus, the shape of the holding portion of the vibration element plate does not require reinforcement or a V-shaped groove, and the vibration element plate is disposed obliquely by improving the manufacturing method.
[0010]
[Embodiments of the Invention]
Embodiments of the present invention will be described below with reference to the accompanying drawings. In each figure, the same numerals indicate the same objects. FIG. 1 shows the state before the cover of the piezoelectric vibrator is put on, and the vibration element plate 2 mounted on the substrate 1 is held in a cantilevered manner. The electrodes of the vibration element plate 2 are not shown, but the vibration element plate 2 It shows a state in which it is held and mounted with an inclination in the longitudinal direction.
[0011]
FIG. 2 shows a flowchart of the method for manufacturing a piezoelectric vibrator of the present invention. Note that the flow of FIG. 2 is described with a focus on the process of holding the vibration element plate 2 which is a feature of the present invention with an adhesive paste 5 (for example, a conductive adhesive or solder) and then drying the adhesive paste 5. is there. The process flow of the manufacturing method of the piezoelectric vibrator that cantilever-holds the vibration element plate 2 using the adhesive on the substrate 1 of the present invention includes (1) mounting the vibration element plate 2 on the substrate 1 and conducting conductive bonding. And (2) reversing the state in which the vibrating element plate 2 is held on the substrate 1 using a reversing jig before the conductive adhesive is cured, and the vibrating element plate 2 is A step of holding the substrate 1 obliquely, and (3) a step of drying and curing the conductive adhesive in the inverted state.
[0012]
2 will be described in detail. (1) In the step of mounting the vibration element plate 2 on the substrate 1 and holding it with a conductive adhesive, it adheres to the holding part 4 of the vibration element plate 2 of the substrate 1 The paste 5 is applied, and the vibration element plate 2 is mounted and held thereon. In this case, if the adhesive paste 5 is applied also to the holding portion of the vibration element plate 2, the adhesive strength is improved.
[0013]
Then, (2) the conductive adhesive is inverted while holding the vibrating element plate 2 to the substrate 1 using an inverted jig even before curing, the vibration element plate 2 with respect to the substrate 1 In the step of holding the substrate diagonally , the substrate 2 is covered with the reversing jig while the vibration element plate 2 is held by the adhesive paste 5, and the substrate 5 is connected to the drying step of the adhesive 5 in the reversed state.
[0014]
In the next step (3) in the step of drying and curing the conductive adhesive in the inverted state, the vibration element plate 2 on the substrate 1 has an inclination with respect to the substrate 1 in accordance with the inclination angle of the inversion jig. The adhesive paste 5 is dried so that it can be fixed in a state. The drying process may be a continuous drying furnace (tunnel furnace) or a batch processing type individual oven drying furnace. Through the above-described series of manufacturing processes, the piezoelectric element is manufactured by holding the vibration element plate 2 in an inclined state with respect to the substrate 1 and covering the vibration element plate 2 with a lid that should be sealed. It is.
[0015]
On the other hand, FIG. 3 is an enlarged perspective view of the mounting portion of the substrate 1 to which the vibration element plate 2 is fixed with the adhesive paste 5. In order to improve the adhesive strength when the vibration element plate 2 is fixed with the adhesive paste 5 at one place on the substrate holding the electrode portion (not shown) of the vibration element plate 2 shown in FIG. A concave dent 3 is provided as a pool portion of 5.
[0016]
As shown in the perspective view of FIG. 3B, contact between the substrate 1 and the adhesive paste 5 of the vibration element plate 2 is achieved by providing a recess 3 in the holding portion 4 (indicated by a dotted line in the drawing) on the substrate 1. By increasing the area, the adhesive strength is improved. This concave shape is a slight dent 3. In the drawing, the dent 3 is expressed as a hole, but any structure may be used as long as the accumulation of the adhesive paste is increased, such as a groove extending in the longitudinal direction of the vibration element plate 2.
[0017]
In the present invention, by using a reversing jig in the reversing step, the vibration element plate 2 can be held obliquely with respect to the substrate 1 and sufficient adhesive paste 5 can be supplied to the front and back holding surfaces of the vibration element plate 2. In order to improve the adhesive strength of the conductive adhesive, the mounting position of the vibration element plate 2 has a concave dent 3, so that the container shape of the piezoelectric vibrator is reduced, and the vibration element plate housed therein It is possible to provide a piezoelectric vibrator that maintains the holding strength even when 2 is reduced.
[0018]
【The invention's effect】
As described above, according to the manufacturing method of the present invention, since the holding strength of the substrate and the vibration element plate can be ensured, sufficient mechanical strength and drop strength can be obtained even when the outer dimensions of the piezoelectric vibrator are reduced. Therefore, peeling of the vibration element plate from the substrate can be improved. As a result, the quality of the piezoelectric vibrator can be improved and the product yield can be improved.
[Brief description of the drawings]
FIG. 1 is a side view showing a bonding form of a vibration element plate of the present invention.
FIG. 2 is a flowchart of the manufacturing method of the present invention.
FIG. 3 is a shape diagram of a holding portion of a substrate to which a vibration element plate of the present invention is fixed.
[Explanation of symbols]
1 Substrate 2 Vibration base plate 3 Dented

Claims (2)

In a method for manufacturing a piezoelectric vibrator that cantilever-holds a vibration element plate using an adhesive on a substrate,
Mounting the vibrating element plate on the substrate and holding it with a conductive adhesive;
Even before the conductive adhesive is cured, reversed while retaining the vibration element plate to the substrate using the reversal jig, the step of holding at an angle the vibrating element plate against the substrate,
Drying and curing the conductive adhesive in the inverted state ;
The manufacturing method of the piezoelectric vibrator containing this.   The method for manufacturing a piezoelectric vibrator according to claim 1, wherein the mounting portion of the vibration element plate has a concave dent in order to improve the adhesive strength of the conductive adhesive.

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