KR100379389B1 - fiber structure and method for fabricating the same - Google Patents

Abstract

The present invention relates to a two-dimensional array type optical fiber fixing structure, comprising a substrate having two-dimensionally arranged optical fiber fixing holes, and an optical fiber inserted into the optical fiber fixing through hole. One side of the optical fiber fixing through-hole is formed to be inclined at an angle so that the width of the outside of the substrate is wide and the width of the inside of the substrate is narrow, and the optical fiber is inserted into the optical fiber fixing through-hole formed in a circular or polygonal shape. Therefore, the uniformity between optical fibers is high, and adjustment of the space | interval between optical fibers is easy.

Description

Fiber structure and method for fabricating the same

The present invention relates to an optical fiber, and more particularly to a two-dimensional array type optical fiber structure and a method of manufacturing the same.

Since the mid-1990s, the amount of communication information has exploded due to the spread of the Internet and electronic commerce.

Dense Wavelength Division Multiplexing (DWDM) optical communication systems have been studied as the most effective and economical method of communicating such a large amount of information, and recently, an early type system has been installed in the field.

In this system, it is necessary to exchange several optical signals. At present, the optical signals are converted into electrical signals and then electrically exchanged.

However, as the capacity of the system increases, there is a need for a cross-connect switch capable of all-optical switching this exchange without photoelectric conversion.

The device has N multiple input optical signals, N multiple input optical signals, and N multiple output optical signals.

In order to couple light to an optical device having multiple inputs and outputs, such as a switch, a structure for fixing an optical fiber in the form of a two-dimensional array is required.

1 is a structural cross-sectional view of a conventional optical fiber structure.

As shown in FIG. 1, first, a V-groove is formed in a silicon substrate in one dimension, and then an optical fiber is inserted and fixed, and a two-dimensional array type multi-fiber structure is formed by stacking them.

In this method, the optical fiber is mounted using a silicon substrate having a V-groove and connected and fixed with epoxy so that both optical fiber cross-section connections are made.

That is, the V-groove is formed in the silicon substrate to align the optical fiber with the V-groove to fix the optical fiber to the substrate.

Therefore, since wire bonding can be excluded, not only the electrical characteristics are excellent, but also the packaging work is simple and mass production is easy.

In this way, the optical fiber is fixed in one dimension and the substrates in which the optical fibers are fixed to the V-grooves are sequentially stacked in the same manner, thereby forming a two-dimensional array type multiple optical fiber structure.

Here, the V-groove for aligning the optical fiber to the substrate is formed by a separate silicon etching process using a precise photolithography process.

The performance of such optical fiber structures is related to the pitch and height uniformity between the optical fibers lying on the V-grooves of the substrate.

However, the optical fiber structure and the manufacturing method according to the related art described above have the following problems.

Conventional two-dimensional multi-fiber structure can obtain excellent uniformity of resolution of photolithography in one lateral direction, but because the thickness of the silicon substrate is fixed, the silicon substrate is mechanically moved in the vertical direction. In the case of lamination, the uniformity is very poor. The spacing between the optical fibers in the vertical direction cannot be freely adjusted.

Accordingly, an object of the present invention is to provide a two-dimensional high-density multi-fiber structure and a method of manufacturing the same having high uniformity between optical fibers and easy adjustment of spacing between optical fibers.

1 is a structural cross-sectional view of a conventional optical fiber structure.

2A is a perspective view of an optical fiber structure according to the present invention;

2b is a sectional view of an optical fiber structure according to the present invention;

Figure 3a to 3f is a cross-sectional view of the manufacturing process of the optical fiber structure according to the present invention.

4a to 4c are cross-sectional views showing the groove shape of the optical fiber structure according to the present invention.

* Explanation of symbols for main parts of the drawings

1: silicon substrate

2, 3: etching mask

4: Home

5: optical fiber

A feature of the optical fiber structure according to the present invention for achieving the above object is to comprise a substrate formed with two-dimensional optical fiber fixing through-holes, and an optical fiber inserted into the optical fiber fixing through-holes. .

Here, one side of the optical fiber fixing through-hole is formed to be inclined at a predetermined angle so that the width of the outside of the substrate is wide and the width of the inside of the substrate is narrow, and the optical fiber is inserted into the optical fiber fixing through-hole formed in a circular or polygonal shape.

Features of the method for manufacturing an optical fiber structure according to the present invention are the first step of forming an etching mask on the upper and lower portions of the substrate, the second step of patterning the mask formed on the lower portion of the substrate to expose the lower surface of the substrate, the substrate A third step of forming a groove by wet etching the bottom surface of the substrate, and a fourth step of patterning a mask formed on the top surface of the substrate to expose the top surface of the substrate at a position corresponding to the groove formed on the bottom surface of the substrate; And a fifth step of dry etching the upper surface of the substrate and penetrating the substrate, and removing the mask and inserting the optical fiber through the groove formed in the lower surface of the substrate.

Here, the third step uses an anisotropic wet etching process, and the fifth step uses a deep reactive ion etching process.

According to the present invention, it is possible to manufacture a structure for fixing high-precision, low-cost, high-capacity two-dimensional multi-fiber optical fibers having excellent uniformity of spacing between optical fibers.

Other objects, features and advantages of the present invention will become apparent from the following detailed description of embodiments taken in conjunction with the accompanying drawings.

A preferred embodiment of an optical fiber structure and a method of manufacturing the same according to the present invention will be described with reference to the accompanying drawings.

First, Figure 2a is a perspective view of a structure for fixing a two-dimensional array type optical fiber according to the present invention.

As shown in Fig. 2A, a silicon substrate is used as the substrate, and through holes through which a two-dimensional N × N array optical fiber can be inserted are formed on the substrate.

At this time, the spacing between the optical fibers to be inserted is determined by the design of the device to be coupled.

FIG. 2B is a cross-sectional view in the thickness direction of the silicon substrate taken along the line AA ′ of FIG. 2A.

As shown in FIG. 2B, the back side of the substrate has a groove formed obliquely using the anisotropic etching characteristic of silicon, which facilitates the insertion of the optical fiber from the back side.

Figure 3a to 3f is a cross-sectional view of the manufacturing process of the optical fiber structure according to the present invention.

First, as shown in FIG. 3A, first and second masks 2 and 3 are formed on and under the silicon substrate 1.

As shown in FIG. 3B, the second mask 3 formed under the substrate 1 is patterned to expose the lower portion of the substrate 1 by using a lithography process.

3C, the lower portion of the substrate 1 is etched using the anisotropic wet etching characteristic of silicon to form the V-groove 4 in the lower portion of the substrate 1.

That is, the formation of the V-groove 4 utilizes the anisotropic etching property of silicon, which uses a characteristic in which the etching rate is significantly different between silicon crystal faces with respect to a specific solution such as KOH.

After that, as shown in FIG. 3D, the first mask 2 formed on the substrate 1 is formed on the lower surface of the substrate 1 using a back-side alignment process using infrared rays. A pattern is formed so as to correspond to (4).

Subsequently, as shown in FIG. 3E, the remaining silicon is completely removed through the substrate 1 using a deep reactive ion etching (Deep RIE) process, which is a dry etching having excellent aspect ratio.

Finally, as shown in FIG. 3F, the first and second masks 2 and 3 used for etching the substrate are removed, and the optical fiber is pushed through the wide V-groove 4 formed in the lower portion of the substrate 1. After the addition, it is fixed by ultraviolet curing or thermosetting epoxy or the like.

4 is a cross-sectional view showing various shapes of grooves formed in the silicon substrate in the optical fiber structure according to the present invention.

On the other hand, as shown in Figure 4, as the groove for the optical fiber can be selected in various forms, such as square, hexagon, rhombus.

The optical fiber structure according to the present invention as described above has the following effects.

It is very easy to insert the optical fiber because the through hole for fixing the optical fiber is wide and gradually decreases to be almost equal to the diameter of the optical fiber.

In addition, even if the alignment of the wet etched groove in the lower part of the substrate and the dry etched groove in the upper surface is misaligned, the optical fiber is automatically fixed to the dry etched straight groove by using the lithography process once the optical fiber is inserted, so that it is transverse and longitudinal. The uniformity of spacing between the optical fibers in the direction is excellent, and it is also easy to adjust the spacing between the optical fibers.

Therefore, it is possible to manufacture a structure for fixing high-precision, low-cost, large-capacity multi-fiber optical fiber, and by applying it to a large-capacity cross-connect switch and the like, it will be possible to further accelerate their commercialization.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the spirit of the present invention.

Therefore, the technical scope of the present invention should not be limited to the contents described in the embodiments, but should be defined by the claims.

Claims (10)

A substrate having through holes for fixing optical fibers arranged in two dimensions; And an optical fiber inserted into the optical fiber fixing through hole. The method of claim 1, One side of the optical fiber fixing through-hole is inclined at a predetermined angle so that the width of the outside of the substrate is wide and the inside of the substrate is narrow. The method of claim 1, And the optical fiber is inserted into the optical fiber fixing through hole. The method of claim 1, The optical fiber fixing through-holes are optical fiber structure, characterized in that the circular shape or polygonal shape. Forming an etching mask on the upper and lower portions of the substrate; Patterning a mask formed on the bottom of the substrate to expose the bottom surface of the substrate; A third step of forming a groove by wet etching the lower surface of the substrate; Patterning a mask formed on the upper surface of the substrate to expose the upper surface of the substrate at a position corresponding to the groove formed on the lower surface of the substrate; Dry etching the upper surface of the substrate to penetrate the substrate; And removing the mask and inserting the optical fiber through the groove formed in the lower surface of the substrate. The method of claim 5, The third step is a method for manufacturing an optical fiber structure, characterized in that using the anisotropic wet etching process. The method of claim 5, The fifth step is a method of manufacturing an optical fiber structure, characterized in that using a deep reactive ion etching (Deep RIE) process. The method of claim 5, After the sixth step, the optical fiber structure manufacturing method characterized in that it further comprises the step of fixing the inserted optical fiber. The method of claim 8, Fixing the optical fiber is a method of manufacturing an optical fiber structure, characterized in that using ultraviolet curing or thermosetting epoxy. The method of claim 5, The fourth step is a method of manufacturing an optical fiber structure, characterized in that using the back-side alignment method using infrared.