JPH03134603A - Adhesion method of high precision - Google Patents

Abstract

PURPOSE:To adhere parts with a high precision by forming grooves on the adhesion surface of parts to be adhered to each other. CONSTITUTION:V grooves 2 are formed in a V-grooved substrate 1 made of Si single crystal by antisotropic etching, and optical fibers 3 are held in V grooves 2. Positions in the Z direction of cores 4 of optical fibers to the surface of the substrate are determined with a high precision. An LiNbO3 substrate 5 is so constituted that its surface where optical waveguides 6 are formed and the surface of the substrate 1 where V grooves 2 are formed are brought into contact with each other. Both surfaces are polished surfaces, and positions of optical waveguides 6 in the Z direction to the surface of the substrate 1 are accurately determined. Alignment marks of substrates 1 and 5 are used to position them in X and Y directions with a high precision. Two substrates are adhered and fixed to each other with an adhesive obtained from grooves 7.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method of bonding various parts that require high precision, such as optical parts.

(Prior art) Conventionally, the common method for bonding parts is to apply adhesive to the bonding surface of one component, and then overlap the bonding surface of the other component on top of this to bond the two parts together. .

(The ridged method that the invention attempts to solve is superior in that it is easy to work with, but because of the presence of adhesive between the two adhesive surfaces, the thickness accuracy of the adhesive parts is teeth,
The drawback is that it necessarily depends on the thickness of the adhesive, and the thicker the adhesive, the lower the accuracy of the thickness.

Therefore, in order to reduce the thickness of the adhesive, the adhesive is dissolved in an appropriate solvent, the diluted adhesive is placed directly on the adhesive surface of the component, and the component is rotated at high speed. A method has been developed in which the adhesive is thinned or sprayed and deposited thinly and uniformly on the adhesive surface, making it easier to obtain an adhesive layer with a thickness of 11 or less.
It has been effective in solving the problems of conventional methods. However, like the conventional method, this method also applies adhesive to one part and then stacks the other part on top of each other, which prevents particles and other foreign matter from adhering to the adhesive after applying the adhesive. Therefore, it is necessary to work in a clean environment such as a clean room or clean booth.Also, even if the thickness is thin, there is an adhesive layer between the adhesive surfaces, so there is a margin of error corresponding to the thickness of the adhesive layer. There is a problem that remains.

The present invention has been proposed in order to improve the above-mentioned drawbacks, and its purpose is to form grooves on one bonding surface of parts to be bonded together, with the same simple operation as the conventional method.
Another object of the present invention is to provide a high-precision bonding method that is not affected by the J7 thickness of the bonding layer.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides that when mutual geometric positioning of components is performed and adhesive fixation is performed, at least one of the first components is fixed on the adhesive surface of the other component. a first part that comes into direct contact with the second part, and a second part that protrudes without contacting the second part, and the first part has a first part that comes into direct contact with the second part. After forming a groove spanning the first part and the second protruding part and positioning the parts, a fluid adhesive is applied onto the groove of the protruding part, and this fluid adhesive travels through the groove. The gist of the invention is a high-precision bonding method characterized in that a first component and a second component are bonded by penetrating into a groove space formed between two components.

(Function) As in the case of ridges, in the present invention, a groove is formed in one part of the surface to be bonded, and after bonding both parts, an adhesive is poured into the groove to bond both parts. Since there is no foreign matter adhering to the adhesive surface or adhesive intervening between the bonding surfaces of two parts, the present invention enables highly accurate bonding (Example) Next, Examples of the present invention I will explain about it. Note that the embodiments are merely illustrative, and it goes without saying that various changes and improvements can be made without departing from the spirit of the present invention.

Next, an example of the present invention will be described, in which a LiNbO3 substrate on which a leading waveguide is formed and a groove substrate for holding and connecting an optical fiber with high precision are bonded with high precision. The purpose of this assembly is to precisely align the core of the optical fiber and the optical waveguide of the LiNbO5 substrate.

Figure 1 shows LiNb0. This figure shows the assembled structure of the substrate, optical fiber, and V-groove substrate, and (A) shows the front view, (B) shows the side view, and (C) shows the top view.

A groove 2 is formed in a silicon single crystal substrate 1 (first component) by anisotropic etching, and an optical fiber 3 is held in contact with the two slopes of the V-groove 2. There is. ■The two slopes of groove 2 are (111) crystal planes of silicon single crystal.■The angle of inclination is exactly 54.7 degrees with respect to the surface of groove substrate 1, and ■The width of groove 2 has excellent dimensional accuracy. Since it is processed by photo-etching, the position of the optical fiber core 4 in the Z direction with respect to the surface of the groove substrate 1 is determined with high precision. 7 is a groove into which adhesive is poured.

On the other hand, LINbO! The substrate 5 (second component) is an optical waveguide 6
The surface where the V-groove 2 is formed is in contact with the surface where the V-groove 2 of the groove substrate 1 is formed. Here, both surfaces are polished surfaces with high precision flatness, so
Similar to the optical fiber 3, the position of the leading waveguide 6 in the Z direction can be accurately determined on the surface of the V-groove substrate 1. Positioning in the X and Y directions is performed in advance by positioning the groove substrate 1 and the LiNb0. By using alignment marks formed on the substrate 5, high accuracy can be ensured.

Note that the groove 7 is a V-groove substrate 1 which is a first component and 1, lNb0. which is a second component. Portion A where the substrate 5 contacts each other
and (2) a portion B where the groove substrate 1 protrudes from the LINbOs substrate 5.

In FIG. 1, the positions of the optical fiber core 4 and the optical waveguide 6 are as follows:
Since the positions of both components in the Z direction are determined with reference to the same surface of the V-groove substrate 1, the configuration is such that both components can be positioned with high precision. In this state, the LiNbts group'
When a fluid UV-curable adhesive is dropped onto a part of the groove 7 protruding from the Fi 5, the adhesive travels through the groove 7 and into the groove space created between the groove substrate 1 and the LINbOs substrate 5. After that, the LiNb01 substrate 5
When ultraviolet rays are irradiated from above, the two substrates remain adhesively fixed.

(Effects of the Invention) According to the present invention, as in the case of soft soil, when mutually geometrically positioning the parts and fixing them with adhesive, at least one of the first
The component has, on its adhesive surface, a first portion that directly contacts the other second component and a second portion that protrudes without contacting the other second component, and the first component includes the second component. After forming a groove spanning the first part that directly contacts the component and the second part that protrudes, and after mutually positioning the parts, attaching a fluid adhesive onto the groove of the protruding part,
This fluid adhesive travels along the groove and penetrates into the groove space created between the two parts, thereby connecting the first part and the second part.
By bonding the two parts together, it is extremely easy to apply the adhesive, and there are no problems such as foreign matter adhering to the adhesive surface or the adhesive intervening between the adhesive surfaces of the two parts, and high precision is achieved. can get. The adhesive used here may be any adhesive as long as it has the fluidity to penetrate through the grooves, and is not limited to UV-curable adhesives.
Furthermore, in the parts assembly configuration shown in FIG. 1, positioning in the Z direction only requires bringing two parts into contact, which has the effect of simplifying the assembly work.

[Brief explanation of the drawing]

FIG. 1 shows an assembled structure of a LiNbO3 substrate, an optical fiber, and a V-groove substrate, with A showing a front view, B a side view, and C a top view. l...Vm substrate 2...■Groove 3...Optical fiber 4...Optical fiber core 5...LINbOs substrate 6...Optical waveguide 7. ····groove

Claims (1)

[Claims] When mutually geometrically positioning the parts and adhesively fixing them, at least one of the first parts does not come into contact with the first part that comes into direct contact with the other second part on its adhesive surface, and the protruding part 2 parts, and said first part.
A groove is formed in the part that spans a first part that directly contacts the second part and a second part that protrudes, and after mutual positioning of the parts, a groove is formed on the groove of the protruding part. The fluid adhesive is applied along the groove and permeates into the groove space formed between the two parts, thereby bonding the first part and the second part. High-precision bonding method.