JPH1090562A - Optical module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to easily execute the alignment between an optical element and an optical connector by fitting and fixing short optical fibers to the V-grooves of an Si substrate and adhering and fixing the optical element to the surface thereof, thereby aligning the optical element and the short optical fibers to each other. SOLUTION: The V-grooves 21 are formed on the surface of the Si substrate 20 and the alignment between the optical element 3 and the short optical fibers 10 is executed. The working of the V-grooves 21 with high accuracy is made possible by subjecting the Si substrate 20 to anisotropic etching. The patterning of the electrodes for electrically connecting the optical element 3 outside and the patterning of the V-grooves 21 are both simultaneously executed by photolithography. A cover 20' consisting of Si or glass formed with the V-grooves nearly similarly with the Si substrate 20 is adhered and fixed to the Si substrate 20 and the short optical fibers 10 are housed between both, by which an optical coupling part 100 is constituted. The sealing of the package is executed by adhering and fixing the optical coupling part 100 by an adhesive to the window formed on the package.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical module, and more particularly, to an optical module for facilitating sealing of a light-passing window of a package of an optical module and alignment between an optical element and an optical fiber outside the module. About the module.

[0002]

2. Description of the Related Art A conventional example will be described with reference to FIG. FIG.
In FIG. 7, the lens 7 is attached to the package 5 with an adhesive 6, and the package 5 of the optical module is provided.
The input and output light of the optical element 3 fixed inside is
To collect light and receive the light, or output the light to an optical connector 9 attached to the outside of the package 5. The reason for adopting such a configuration that the light input / output to / from the optical element 3 is received via the lens 7 or is incident on the optical connector 9 is that the light emitted or output from the optical element 4 is largely diffused. However, high efficiency optical coupling between the optical element 3 and the optical connector 9 cannot be realized unless the light is focused.

Referring to FIG. 5, in this conventional example, an optical fiber 10 is directly drawn into an optical module package 5 without using a lens, and a core end face is positioned very close to an optical element 3. Thus, the optical fiber 10 is fixed to the package 5.

[0004]

In the conventional example of the optical module described above, when the input / output light of the optical element 3 is guided between the optical connector 9 through the lens 7, the optical element 3, the lens 7, Three mutually independent parts called optical connectors 9 must be aligned with one another. Furthermore,
The lens 7 has an effect of improving the optical coupling efficiency between the optical element 3 and the optical connector 9 by the light condensing function, but the optical element 3 and the optical connector 9 must be accurately positioned at the focal position. Unless the accuracy of the alignment is ensured, there is a problem that the loss of optical coupling between the two becomes large. Accordingly, when the mutual alignment between the optical element 3 and the optical connector 9 is performed via the lens 7, the alignment accuracy is such that the optical fiber 10 is directly in the vicinity of the optical element 3 without using the lens 7. Higher accuracy is required as compared to the case where the end position of the core wire is determined and the mutual alignment between the optical element 3 and the optical connector 9 is performed. In particular, when the optical element 3 is an array-type optical element including a plurality of light emitting units, it becomes more difficult to align the optical element 3 with the optical connector 9 or the optical fiber 10.

In the conventional example shown in FIG. 5, a lens is not required, but the optical fiber 10 is fixed to the package 5 of the optical module. Come inconvenience.
The present invention provides an optical module that solves the above problems.

[0006]

SUMMARY OF THE INVENTION In an optical module for inputting and outputting light to and from an optical element using an optical fiber having an optical connector 9, one surface is subjected to anisotropic etching to form a V-groove 21 with a Si groove. A short optical fiber that is provided with the substrate and that is bonded and fixed to one surface of the Si substrate in the vicinity of one end of the V-groove; A Si cover 20 ′ which is anisotropically etched on one surface to form a V-groove 21 and is adhered and fixed to one surface of the Si substrate 20;
A package 5 is provided for holding an intermediate portion of the Si substrate 20 on which the window 51 is formed and the Si cover 20 ′ is adhesively fixed and fixed to the window, and protrudes from the package 5 of the Si substrate 20 and the Si cover 20 ′. Optical connector 9
An optical module for connecting the two was constructed.

Then, a guide pin V-groove 22 is formed on one surface of the Si substrate 20, and an optical module is formed in which a guide pin 31 for guiding the optical connector 9 is fitted and fixed in the guide pin V-groove 22. The optical element 3 is a one-dimensional array-type optical element including a plurality of elements. On one surface of the Si substrate 20, a plurality of V-grooves 21 corresponding to each element of the one-dimensional array-type optical element are formed. An optical module in which the short optical fiber 10 was fitted and fixed in each of the V grooves 21 was configured.

Further, the short optical fiber 10 constitutes an optical module which is a single mode optical fiber whose core diameter is enlarged over its entire length. An optical module in which the upper and lower surfaces and side surfaces of both the Si substrate 20 and the cover 20 ′ and the periphery of the window 51 are metallized to adhesively fix the Si substrate 20 and the cover 20 ′ and adhesively fix these to the window 51. Was configured.

[0009]

An embodiment of the present invention will be described with reference to FIG. FIG. 1 is a perspective view showing an optical coupling section 100 in which an optical element 3 and a short optical fiber 10 are bonded and fixed to the surface of a Si substrate 20 of an optical module. A V-groove 21 is formed on the surface of the Si substrate 20, and alignment between the optical element 3 and the short optical fiber 10 is performed. The illustrated optical element 3 is an array-type optical element having four channels, and the short surfaces of four short optical fibers 10 face each other. The V groove 21 can be processed with high accuracy of ± 1 μm or less by anisotropically etching the Si substrate 20. Then, the patterning of the electrode for electrically connecting the optical element 3 to the outside and the patterning of the V-groove 21 are simultaneously performed by photolithography. Since the mutual positional relationship between the electrode and the V-groove 21 itself and the two are defined with high precision by photolithography, the optical element 3 is mounted and fixed on the electrode formed on the surface of the Si substrate 20 as a mark.
In a state where the short optical fiber 10 is fitted in the V-groove 21, the end face of the short optical fiber 10 is opposed to the optical element 3, and the short optical fiber 10 is bonded and fixed to the V-groove 21. The mutual alignment with the optical fiber 10 is naturally performed with high accuracy.

A short optical fiber 1 is provided on the surface of the Si substrate 20.
A guide pin V-groove 22 for bonding and fixing the guide pin 31 is also formed in addition to the V-groove 21 for fitting and fixing 0. The guide pins 31 bonded and fixed to the guide pin V-grooves 22 are used to perform a fitting position alignment with the external optical connector 9. As the optical connector 9 guided by the guide pin 31, an MT connector which is JIS standardized as an F12 type is used, and the shape and pitch of the guide pin 31 are designed according to the MT connector. The MT connector can be easily connected to the optical coupling section 100 of the optical module. Therefore, the fitting position between the four-channel array type optical element 3 and the optical connector 9 can be easily adjusted.

As described above, the V-groove 2 is formed on the surface of the Si substrate 20.
1 and a guide pin V-groove 22 to form a short optical fiber 1
0 and the guide pins 31 are bonded and fixed, and the optical element 3 is bonded and fixed.
1 and a cover 20 ′ made of Si or glass formed with a guide pin V groove 22 are adhered and fixed to the Si substrate 20, and the short optical fiber 10 and the guide pin 31 are housed between the two to form the optical coupling section 100. You.

FIG. 2 is a view showing a state where the optical coupling unit 100 is attached to the package 5 of the optical module. The optical coupling unit 100 seals the package 5 by adhesively fixing the optical coupling unit 100 to a window 51 formed in the package 5 with an adhesive 6. By metallizing the upper and lower surfaces and side surfaces of both the Si substrate 20 and the cover 20 ′ and the periphery of the window 51, the above-described bonding and fixing between the Si substrate 20 and the cover 20 ′ and the formation of the window 51 by the optical coupling unit 100 are performed. Sealing can be performed simultaneously by soldering, and the manufacturing process can be simplified.

FIG. 3 is a diagram for explaining an optical fiber.
Denotes an optical fiber core, and 2 denotes an optical fiber cladding. (A) is a figure which shows the cross section of the length direction of a single mode optical fiber. The single mode optical fiber has a very thin core 1 having a diameter of about 10 μm,
Difficulty positioning with other opponents. Here, referring to (b), when the end of the single mode optical fiber is heated from the outside to diffuse the material of the core 1 to the periphery, the diameter of the core 1 can be increased to about 40 μm, Matching becomes easier. The optical fiber processed in this manner is a TEC (Thermally-diff).
It has been commercialized as a used expanded core) optical fiber. By the way, since the bending loss increases when the core 1 is enlarged, the enlargement processing has been applied only to an extremely short region from the end face of the optical fiber. However, according to the present invention, since the optical fiber fixed to the V-groove on the Si substrate is not bent and used, a TEC optical fiber whose core diameter is enlarged over its entire length is used. The optical fiber to be attached to the external optical connector 9 also has this T
By using an EC optical fiber, the optical element 3 and Si
Alignment between the short optical fiber 10 fixed to the surface of the substrate 20 and the optical connector is greatly facilitated.

[0014]

As described above, according to the present invention, a short optical fiber is fitted and fixed in a V-groove of a Si substrate whose surface is subjected to high-precision V-groove processing, and an optical element is bonded and fixed to this surface. The optical element and the short optical fiber are aligned to perform optical alignment between the optical element and an external optical connector by mounting the optical element on a package of the optical module. Alignment with the connector can be easily performed.

[Brief description of the drawings]

FIG. 1 is a perspective view illustrating an embodiment.

FIG. 2 is a diagram illustrating sealing of an optical module.

FIG. 3 is a cross-sectional view illustrating a short optical fiber with an enlarged core.

FIG. 4 is a diagram illustrating a conventional example.

FIG. 5 is a diagram illustrating another conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Core 2 Cladding 3 Optical element 4 Heat sink 5 Package 6 Adhesive 7 Lens 8 Sleeve 9 Optical connector 10 Short optical fiber 20 Si substrate 20 'Cover 21 V groove 22 Guide pin V groove 31 Guide pin 51 Window 100 Optical coupling part

Claims (5)

[Claims] 1. An optical module for inputting / outputting light to / from an optical element using an optical fiber having an optical connector, comprising: a Si substrate having one surface subjected to anisotropic etching to form a V groove; An optical element that is bonded and fixed to one surface of the Si substrate in the vicinity of one end of the groove; a short optical fiber that is bonded and fixed to the V groove; and an anisotropic etching is performed on one surface Forming a V-groove to form a V-groove and bonding and fixing the Si cover to one surface of the Si substrate. A window is formed and the intermediate portion of the Si substrate to which the Si cover is bonded and fixed is bonded and fixed to the window. An optical module comprising a package to be held, wherein an optical connector is connected to an end face of the Si substrate and the Si cover projecting from the package. 2. The optical module according to claim 1, wherein a guide pin V-groove is formed on one surface of the Si substrate, and a guide pin for guiding the optical connector is fitted and fixed in the guide pin V-groove. Optical module with features. 3. The optical module according to claim 1, wherein the optical element is a one-dimensional array type optical element including a plurality of elements, and is provided on one surface of the Si substrate. An optical module, wherein a plurality of V-grooves corresponding to each element of a one-dimensional array type optical element are formed, and a short optical fiber is fitted and fixed to each of the V-grooves. 4. The optical module according to claim 1, wherein the short optical fiber is a single mode optical fiber whose core diameter is enlarged over its entire length. Optical module. 5. The optical module according to claim 1, wherein upper and lower surfaces and side surfaces of both the Si substrate and the cover, and the periphery of the window are metallized to form the Si substrate and the cover. An optical module, wherein the optical module is bonded and fixed to a window and the windows are bonded and fixed.