Optical module

Abstract

To provide a component for an optical device for easily bonding and fixing a tube at an appropriate position, and an optical module including the component.SOLUTION: A component is used for connecting a silicon chip (23) integrated on a device substrate (10) and an optical fiber (20) includes: a planar top portion (31a), and a first side portion (31b) and a second side portion (31c) substantially perpendicular to the top portion; a recess formed of the top portion, the first side portion, and the second side portion, and accommodating a fiber block (21) holding the optical fibers (20), the recess having an opening for the second side portion to draw out the optical fiber in a drawing direction; and a pressing portion (50) that is formed on the top portion and being substantially perpendicular thereto, the pressing portion being brought into contact with an end of a tube (22) having a hollow portion through which the optical fiber passes.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to an optical module, and more particularly to a component used in a connection portion between an optical device and an optical fiber, and an optical module including the component. [Background technology]

[0002] Conventionally, optical transmitter / receiver modules in networks are required to be smaller, consume less power, and have higher transmission speeds. Coherent Optical Subassembly (COSA), an optical module for digital coherent that integrates optical transmitter and receiver circuits on a small silicon chip and packages this together with electronic circuits such as amplifiers, is expected to be a device that can achieve these goals.

[0003] Fig. 1 shows a conventional COSA 100. Fig. 1(a) is a perspective view from above, Fig. 1(b) is a perspective view from below, Fig. 1(c) is a perspective view from below of the input / output section of COSA 100, and Fig. 1(d) is a cross-sectional view of the input / output section of COSA 100 taken along the section line Id-Id. Note that the BGA (ball grid array) side of the device substrate 10 constituting COSA 100 is referred to as the bottom surface.

[0004] As shown in Fig. 1, COSA 100 has a device substrate 10 on which a silicon chip 23 including a waveguide utilizing silicon photonics technology is integrated, and a lid 30 for protecting them. Fig. 1 also shows an optical fiber 20 that is optically connected to the waveguide formed on the surface of the silicon chip 23. The silicon chip 23 is integrated such that the surface on which the waveguide is formed faces the lower surface side of the device substrate 10.

[0005] The fiber block 21 is directly fixed to the silicon chip 23 so that the optical fiber 20 is connected to the waveguide of the silicon chip 23 through the fiber block 21. As shown in FIG. 1(d), the fiber block 21 does not contact the lid 30 and has a small gap between the lid 30 and the optical fiber 20. In FIG. 1, the optical fiber 20 is a ribbon core wire in which a plurality of optical fibers are aligned. The tips of the core wires of the optical fiber 20 are arranged along the V-groove of the fiber block 21. FIG. 1 also shows a fiber protection resin 24 arranged opposite the V-groove of the fiber block 21. The optical fiber 20 is fixed between the V-groove and the fiber protection resin 24. The tips of the core wires extend through the V-groove to the end face of the fiber block 21. The end face of the silicon chip 23 and the end face of the fiber block 21 are connected and fixed opposite to each other. In order to prevent reflection at the end face of the silicon chip 23, the direction of the waveguide near the end face of the silicon chip 23 is not perpendicular to the end face (not in the X direction). The extending direction of the optical fiber 20 is also not perpendicular to the end face of the silicon chip 23 .

[0006] The lid 30 shown in FIG. 1 has an optical fiber coupling portion protection portion 31 for protecting the coupling portion between the optical fiber 20 and the waveguide formed on the surface of the silicon chip 23 .

[0007] Fig. 2 shows a conventional optical fiber coupling protection part 31. Fig. 2(a) is a perspective view from the bottom of the input / output part of COSA 100 similar to Fig. 1(c), Fig. 2(b) is a cross-sectional view in the extension direction of the optical fiber 20 taken along the cross-sectional line IIb-IIb, Fig. 2(c) is a plan view from the bottom of a portion of the optical fiber coupling protection part 31, and Fig. 2(d) is a cross-sectional view of a portion of the optical fiber coupling protection part 31 taken along the cross-sectional line IId-IId.

[0008] The optical fiber coupling protection part 31 has a flat upper part 31a and side parts 31b and 31c which are approximately perpendicular to the upper part 31a in three directions around the fiber block. As shown in Fig. 2(a), the fiber block 21 is housed in a space formed by the upper part 31a, the side parts 31b and 31c. The side part 31c has an opening for passing the optical fiber 20 through.

[0009] The optical fiber 20 is weak against a force perpendicular to the stretching direction. Therefore, as shown in Fig. 2, a tube 22 is provided to protect the optical fiber 20 so that the optical fiber 20 does not directly contact the opening. The optical fiber 20 passes through the tube 22 and is fixed to the fiber block 21.

[0010] The inner diameter of the tube 22 is sufficiently larger than the sum of the diameters of the individual core wires of the optical fiber 20. Therefore, the tube 22 is freely movable in the extending direction of the optical fiber 20. For this reason, the tube 22 is fixed to the optical fiber coupling portion protection portion 31 so as not to move.

[0011] 3 is a cross-sectional view of the opening in side portion 31c taken along line III-III in FIG. 2(a). The opening has a top portion 32a and a side portion 32b. Tube 22 is disposed to pass through the opening and is bonded and fixed by adhesive 40 inserted between tube 22 and the opening.

[0012] FIG. 4 is an enlarged bottom view of the opening of the side portion 31c of the optical fiber coupling portion protection portion 31. The adhesive 40 for bonding and fixing the tube 22 to the opening is injected in the order of (1) to (4) in FIG. 4. First, the fluid adhesive 40 is injected between the side portion 32b and the tube 22 from the tip position of the triangle shown in (1) to (2), and the tube 22 is temporarily fixed as shown in FIG. 3. Next, the adhesive 40 is added from the tip position of the triangle shown in (3) to (4), and the adhesive 40 is injected to the upper part of the tube 22 and the outside of the opening, forming fillets 40a and 40b. The dashed rectangle in FIG. 4 indicates the fillet 40a on the opposite side of the upper part 32a of the tube 22, and the dashed trapezoid indicates the fillet 40b on the outside of the opening of the side portion 31c (32b) of the tube 22. The optical fiber 20 extends from the outside to the inside of the opening of the side portion 31c through the inside (hollow portion) of the tube 22. The portion of the optical fiber 20 from which the coating has been removed and which protrudes from the hollow portion of the tube 22 (the bare core wire located from the outside to the inside of the opening of the side portion 31c) is fixed in a sandwiched state between the V-groove of the fiber block 21 and the fiber protection resin 24.

[0013] In the manufacture of an optical module, the process of positioning the tip of the tube 22 on the fiber block 21 side and fixing it to the opening is an important process. If the distance between the fiber block 21 and the tip of the tube 22 is too short, the optical fiber coupling part protection part 31 expands and contracts due to the effect of heat in the subsequent reflow process, and the tip of the tube 22 moves, exerting pressure on the fiber block 21. As a result, the possibility of a coupling loss occurring between the optical fiber 20 and the waveguide formed on the surface of the silicon chip 23 is increased. On the other hand, if the distance between the fiber block 21 and the tip of the tube 22 is too long, for example when the tip of the tube 22 is located inside the opening, the fixing of the tube 22 by the adhesive 40 may be insufficient, resulting in a decrease in reliability. Furthermore, if the adhesive 40 adheres to the exposed optical fiber 20 between the fiber block 21 and the tube 22, or if the adhesive 40 flows into the hollow part of the tube 22 and bonds and fixes the tube 22 and the optical fiber 20, the optical fiber 20 may be damaged by the stress of the expansion and contraction of the optical fiber coupling part protection part 31 generated in the subsequent reflow process.

[0014] To prevent this, it is necessary to position the tip of the tube 22 having a predetermined length at a predetermined position. For example, it is necessary to check whether the distance between one tip of the tube 22 having a predetermined length (e.g., 3.6±0.3 mm) and the fiber block 21 is within a predetermined range (e.g., 0.25 mm to 0.5 mm). At the same time, it is also necessary to check whether the other tip of the tube 22 is within a predetermined range (e.g., 2 mm or less) outside the opening of the side portion 31c of the optical fiber coupling portion protection portion 31. Summary of the Invention [Problem to be solved by the invention]

[0015] Therefore, the process of positioning the tip of the tube 22 on the fiber block 21 side and the process of fixing the tube 22 to the opening of the optical fiber coupling protection portion 31 with adhesive 40 required delicate work under a microscope, which was extremely inefficient.

[0016] The present invention has been made in consideration of such problems, and its object is to provide a part for an optical device that allows a tube to be easily adhesively fixed in an appropriate position, and an optical module equipped with the part. [Means for solving the problem]

[0017] A component according to one embodiment of the present invention is a component used for connecting an optical fiber to a silicon chip integrated on an optical device substrate, the component having a flat upper portion, a first side portion and a second side portion substantially perpendicular to the upper portion, a recess portion formed by the upper portion, the first side portion and the second side portion, and a pressing portion formed at a predetermined position of the upper portion within the recess portion and substantially perpendicular to the upper portion.

[0018] The component in one embodiment further includes a tube having a hollow portion through which the optical fiber passes, the tube being placed in the opening of the second side portion, and the pressing portion is formed in a position where a portion of the tube abuts but does not contact the optical fiber.

[0019] In one embodiment, the pressing portion is formed to abut against a part of the tube at one location.

[0020] In one embodiment, the pressing portion is formed so as to come into contact with a part of the tube at two points.

[0021] In one embodiment, the pressing portion that comes into contact with a part of the tube at two points is connected at the upper side.

[0022] The component in one embodiment further includes an adhesive receiving portion formed between the pressing portion and the opening.

[0023] In one embodiment of the component, the adhesive containing portion is formed by cutting further than the surface on which the pressing portion is formed.

[0024] An optical module according to one embodiment of the present invention includes any one of the above-described components, an optical device substrate, and a waveguide formed on a surface of a silicon chip, and the waveguide and an optical fiber are optically coupled at an end face of the silicon chip. Effect of the Invention

[0025] As described above, according to one embodiment of the present invention, it is possible to easily adhesively fix a tube to a predetermined position of an optical device component by using a pressing portion of the optical device component, and it is also possible to efficiently manufacture an optical module including an optical device component having a pressing portion. [Brief description of the drawings]

[0026] [Figure 1] FIG. 1 shows a conventional optical module for digital coherent (Coherent Optical SubAssembly: COSA), where (a) is a perspective view from above, (b) is a perspective view from below, (c) is a perspective view from below of the input / output section of the COSA, and (d) is a cross-sectional view of the input / output section of the COSA along the Id-Id section line. [Diagram 2] 1A and 1B are diagrams showing a conventional optical fiber coupling protection section, in which (a) is an oblique view from the bottom of the input / output section of a COSA, (b) is a cross-sectional view in the extension direction of the optical fiber at the IIb-IIb cross-sectional line, (c) is a plan view from the bottom of a portion of the optical fiber coupling protection section, and (d) is a cross-sectional view of a portion of the optical fiber coupling protection section at the IId-IId cross-sectional line. [Diagram 3] 3 is a cross-sectional view of a side opening of the conventional optical fiber coupling protection part taken along the line III-III in FIG. 2. [Figure 4] 1 is an enlarged top view of an opening on a side of a conventional optical fiber coupling protection part. [Diagram 5]1A is a diagram showing an optical fiber coupling protection section of an optical module (COSA) according to one embodiment of the present invention, in which (a) is an oblique view from the bottom of the input / output section of the COSA, (b) is a cross-sectional view in the extension direction of the optical fiber at the Vb-Vb cross-sectional line, (c) is a plan view from the bottom of a portion of the optical fiber coupling protection section, and (d) is a cross-sectional view of a portion of the optical fiber coupling protection section at the Vd-Vd cross-sectional line. [Figure 6] 6A and 6B are diagrams showing a first example of a pressing portion of an optical fiber coupling protection portion of a COSA according to an embodiment of the present invention, in which (a) is a plan view in the bottom direction, (b) is a cross-sectional view along the VIb-VIb cross-sectional line, and (c) is a cross-sectional view along the VIc-VIc cross-sectional line. [Figure 7] 7A and 7B are diagrams showing a second example of the pressing portion of the optical fiber coupling protection portion of a COSA according to one embodiment of the present invention, in which (a) is a plan view in the bottom direction, (b) is a cross-sectional view along the VIIb-VIIb cross-sectional line, and (c) is a cross-sectional view along the VIIc-VIIc cross-sectional line. [Figure 8] 8A to 8C are diagrams showing a third example of the pressing portion of the optical fiber coupling portion protection portion of a COSA according to one embodiment of the present invention, in which (a) is a plan view in the bottom direction, (b) is a cross-sectional view, and (c) is a cross-sectional view along the VIIIc-VIIIc cross-sectional line. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. The same or similar reference numerals indicate the same or similar elements, and repeated description may be omitted. The materials and values ​​in the following description are merely examples, and the present invention can be implemented using other materials and values. Hereinafter, an optical module for digital coherence (COSA) will be exemplified as an optical device. It goes without saying that the present invention can be implemented in any optical device other than COSA without departing from the gist of the present invention. In the following description, the lid 30 side of the optical module 100 will be expressed as the upper direction, and the device substrate 10 side as the lower direction.

[0028] Fig. 5 is a diagram showing an optical fiber coupling section protection section 31 of a COSA according to an embodiment of the present invention. The optical fiber coupling section protection section 31 constitutes a part of the lid 30 described with reference to Fig. 1. As described above, the optical fiber coupling section protection section 31 is a component for an optical device that protects the coupling section between the optical fiber 20 and the waveguide formed on the surface of the silicon chip 23. The optical fiber coupling section protection section 31 may be formed integrally with the lid 30 that protects the device substrate 10 on which the silicon chip 23 is integrated, or may be formed separately.

[0029] The protective lid 30 can be formed by machining a metal plate. When the lid 30 and the optical fiber coupling part protection part 31 are formed separately, if the lid 30 is made of metal, the material of the optical fiber coupling part protection part 31 can also be ceramic or resin. In consideration of heat dissipation from the device substrate 10 on which the silicon chip 23 is integrated, the lid 30 is preferably made of a metal with high thermal conductivity. In this embodiment, the optical fiber coupling part protection part 31 is formed integrally with the lid 30 by machining a metal plate.

[0030] The optical fiber coupling protection part 31 of this embodiment also has a flat upper part 31a and side parts 31b and 31c that are substantially perpendicular to the upper part 31a so as to surround the fiber block, similar to the conventional optical fiber coupling protection part 31. As shown in FIG. 5(a), the fiber block 21 is accommodated in a space (recess) formed by the upper part 31a, the side parts 31b, and the side parts 31c. The fiber block 21 does not contact the upper part 31a, and there is a gap between them. The side part 31c has an opening. The opening has an opening with a diameter approximately equal to that of the tube 22. In FIG. 5(d), the shape of the opening in which the tube 22 is accommodated as viewed from the extension direction of the optical fiber 20 is rectangular, but it may be U-shaped. Furthermore, the side wall of the opening facing the tube 22 may be a surface parallel to the extension direction of the optical fiber 20, or may be a shape that expands from the inside to the outside. In the latter case, the effect of suppressing the injected adhesive 40 from leaking out to the upper part 31a on the inside is high.

[0031] As shown in FIG. 5, the optical fiber coupling protection part 31 of the present embodiment differs from the conventional optical fiber coupling protection part 31 shown in FIG. 2 in that a pressing part 50 that is approximately perpendicular to the upper part 31a is formed near the side part 31c having an opening.

[0032] The pressing part 50 is formed so that the end of the tube 22 is located at a predetermined position (i.e., an appropriate position of the end of the tube 22). The tube 22 is inserted from the outside of the side part 31c into the inside of the side part 31c through the opening, and the tube 22 is fixed at a position where at least a part of the tube 22 abuts against the pressing part 50. When the end of the tube 22 abuts against the pressing part 50, the end of the tube 22 is located inside the optical fiber coupling part protection part 31 from the opening of the side part 31c, and the other end is located outside the side part 31c. Therefore, it is not necessary to perform delicate positioning under a microscope, and it is possible to easily perform highly accurate positioning in a short time. By bonding the tube 22 to the opening of the side part 31c in this state with the adhesive 40, the tube 22 is fixed over the entire thickness of the opening, and the problem of reduced reliability caused by insufficient adhesive fixation is solved.

[0033] Excess adhesive when bonding the tube 22 falls onto the upper part 31a between the opening and the pressing part 50. If the fallen adhesive enters the gap between the fiber block 21 and the upper part 31a and fixes the fiber block 21 and the upper part 31a, force will be applied to the joint between the fiber block 21 and the silicon chip 23 as the lid 30 expands during the reflow process, which may cause misalignment of the optical axis or a deterioration in the fixing strength of the fiber block 21. For this reason, it is desirable to prevent the fallen excess adhesive from entering the fiber block 21 side.

[0034] In this embodiment, when the pressing portion 50 is formed by cutting, both ends of the pressing portion 50 are in contact with the side portion 31c. As a result, a closed area (hereinafter, adhesive storage portion 51) is formed by the pressing portion 50 and the side portion 31c in the upper portion 31a. As shown in FIG. 5(d), the area where the excess adhesive falls can be surrounded by a wall to prevent the fallen adhesive from spreading. The adhesive storage portion 51 is formed between the pressing portion 50 and the opening of the side portion 31c. The outer wall of the adhesive storage portion 51 includes at least the pressing portion 50 and the side portion 31c of the area where the opening is formed. In other words, the opening side portion of the pressing portion 50 and the opening portion of the side portion 31c facing it constitute a part of the adhesive storage portion 51. In FIG. 5(d), the pressing portion 50 is formed to surround the opening, and both ends thereof are in contact with parts of the side portion 31c. In other words, when the adhesive containing portion 51 is produced by cutting, a part of the side wall of the adhesive containing portion 51 is used as the pressing portion 50 .

[0035] From the viewpoint of preventing the dropped adhesive from spreading over the upper portion 31a and entering the gap between the fiber block 21 and the upper portion 31a, a groove may be formed by cutting deeper (reducing the thickness from the back surface of the upper portion 31a) between the pressing portion 50 and the region where the opening is formed, so that the groove becomes at least a part of the adhesive containing portion 51. The groove will be described later.

[0036] The structure of the adhesive storage section 51 can be exemplified as follows. The thickness H1 of the opening of the side section 31c (thickness from the back surface of the upper section 31a to the bottom surface of the opening) is 0.9 mm. The thickness H2 of the adhesive storage section 51 of the side section 31c (thickness from the back surface of the upper section 31a to the bottom surface of the adhesive storage section 51) is 0.6 mm. The thickness H3 of the pressing section 50 (thickness from the back surface of the upper section 31a to the tip of the pressing section 50) is 1.15 mm. The thickness H4 of the recess of the side section 31c (thickness from the bottom surface of the side section 31c to the bottom surface of the opening) is 1.05 mm.

[0037] The length of the tube 22 (in the extending direction of the optical fiber 20) is 2.0 mm. The outer diameter of the tube 22 is 0.9 mm. The inner diameter of the tube 22 is 0.82 mm. The thickness of the tube 22 is 0.04 mm. The width of the opening of the side portion 31c is 1.2 mm. The distance between the tube 22 and the opening is 0.15 mm.

[0038] The length L1 of the opening of the side portion 31c (in the extension direction of the optical fiber 20) is 1.75 mm. The distance L2 between the opening side portion of the pressing portion 50 and the opening of the side portion 31c (the distance in the extension direction of the optical fiber 20 of the adhesive containing portion 51) is 0.6 mm. The length L3 of the pressing portion 50 (in the extension direction of the optical fiber 20) is 0.2 to 0.3 mm. The distance L4 between the pressing portion 50 and the fiber block 21 is 0.347 mm.

[0039] In a state where the end of the tube 22 is in contact with the pressing portion 50, when the adhesive 40 is inserted into the gap between the tube 22 and the side portion 31c in the manner described with reference to Fig. 4, excess adhesive flows down into the adhesive storage portion 51. Since the optical fiber 20 is covered with the tube 22 up to the pressing portion 50, excess adhesive 40 falls from both sides of the tube 22 near the opening before reaching the pressing portion 50, so that the adhesive 40 does not adhere to the exposed optical fiber 20 between the fiber block 21 and the tube 22, or flow into the hollow portion of the tube 22 (i.e., the tube 22 and the optical fiber 20 are bonded by the adhesive 40 in the hollow portion).

[0040] In this way, the optical fiber coupling protection part 31 of this embodiment facilitates the process of positioning the tip of the tube 22 on the fiber block 21 side and the process of fixing the tube 22 to the opening of the side part 31c of the optical fiber coupling protection part 31 with adhesive 40.

[0041] Hereinafter, the optical fiber coupling protection section 31 according to the first to third embodiments will be described with reference to FIGS.

[0042] Example 1 FIG. 6 is a diagram showing an optical fiber coupling protection part 31 of a COSA according to an embodiment of the present invention. FIG. 6(a) is a schematic plan view of a part of the optical fiber coupling protection part 31 seen from the lower surface side. FIG. 6(b) is a schematic cross-sectional view of a part of the optical fiber coupling protection part 31 taken along the VIb-VIb cross-sectional line. FIG. 6(c) is a cross-sectional view taken along the VIc-VIc cross-sectional line. The rectangular pressing part 50 is formed on the upper part 31a at a position spaced apart from the opening on the inside of the optical fiber coupling protection part 31 and substantially perpendicular to the upper part 31a. An adhesive container 51 is formed between the side part 31c and the pressing part 50. The pressing part 50 constitutes a part of the side wall of the adhesive container 51. As shown in FIG. 6(b), the adhesive container 51 is cut so as to be deeper (so as to be thinner from the upper surface 31TS of the upper part 31a) than in the example shown in FIG. 5(d). 6, the width W of the rectangular pressing part 50 is the same as the width of the opening, but it may be narrower than the width of the opening as long as it is a width that abuts against part of the tube 22, but it is better for it to be wider than the diameter of the tube 22. This is to prevent excess adhesive that has dropped from the tube 22 from passing beside the pressing part 50 and spreading toward the fiber block 21. Also, the center of the width W is arranged to be the center of the opening of the optical fiber coupling part protection part 31, but it is not necessary to arrange it to be the center of the opening as long as it is a position where part of the tube 22 abuts.

[0043] An example of the positional relationship between the pressing part 50 and the opening is as follows. The thickness H1 of the opening of the side part 31c (thickness from the upper surface 31TS of the optical fiber coupling part protection part 31 to the position 31cBS of the opening) is 0.9 mm, and the thickness H3 of the pressing part 50 (thickness from the upper surface 31TS of the optical fiber coupling part protection part 31 to the tip 50BS of the pressing part 50) is 1.15 mm. Therefore, as shown in FIG. 6, when the tube 22 is inserted into the opening of the side part 31c, a part of the end of the tube 22 abuts against the pressing part 50 and stops. On the other hand, the inner diameter of the tube 22 is 0.82 mm and the thickness is 0.04 mm, and the optical fiber 20 passes through the inside of the tube 22 facing the abutment part, so that it can pass through a position sufficiently away from the tip of the pressing part 50. If the thickness H3 of the pressing part 50 is too large, there is a risk that the tip of the pressing part 50 and the optical fiber 20 will come into contact with each other, so it is desirable that the tip of the pressing part 50 is located at a height approximately equal to the center of the tube 22. In this manner, the fiber block 21 is fixed to the end face of the silicon chip 23 in an optically coupled state.

[0044] With a part of the end of the tube 22 in contact with the pressing part 50, the tube 22 is temporarily fixed to the opening of the optical fiber coupling part protection part 31 using the adhesive 40 as described with reference to FIG. 4, and then the fillets 40a and 40b are formed. The end of the tube 22 in contact with the pressing part 50 is in a predetermined appropriate position (i.e., a position where the adhesive 40 can be prevented from adhering), so positioning under a microscope is not necessary. In addition, when the tube 22 is in contact with the pressing part 50, the length of the tube 22 from the opening to the pressing part 50 is sufficient, so that the excess adhesive 40 flows down from both sides of the tube 22 into the adhesive storage part 51 near the opening without reaching the pressing part 50, and therefore the adhesive 40 does not adhere to the optical fiber 20. The pressing part 50 in the first embodiment has a wide and low rectangular surface perpendicular to the extension direction of the optical fiber 20, but may have other shapes as exemplified below.

[0045] Example 2 With reference to Fig. 7, the pressing portion 50a, which is a narrow, tall rectangle whose surface perpendicular to the extending direction of the optical fiber 20 is described. The configuration of Example 1 in Fig. 6 has one pressing portion 50, whereas the configuration of Example 2 differs from that of Example 1 in that it has two columnar pressing portions 50a. Fig. 7 is a diagram showing an optical fiber coupling portion protection portion 31 of a COSA according to an embodiment of the present invention. Fig. 7(a) is a schematic plan view of the lower surface side of a portion of the optical fiber coupling portion protection portion 31. Fig. 7(b) is a cross-sectional view of a portion of the optical fiber coupling portion protection portion 31 taken along the VIIb-VIIb cross-sectional line. Fig. 7(c) is a cross-sectional view taken along the VIIc-VIIc cross-sectional line.

[0046] 7, the two pressing parts 50a are formed substantially perpendicularly on the upper part 31a of the optical fiber coupling part protection part 31 at a position on the device substrate 10 (not shown) side spaced apart from the side part 31c having the opening of the optical fiber coupling part protection part 31. In this Example 2, an adhesive storage part 51 is formed in the upper part 31a by cutting between the pressing parts 50a, including a region into which excess adhesive falls, and the opening. In this Example 2, the two pillar-shaped pressing parts 50a are connected by a part cut into a rectangular plate shape, which constitutes a part of the side wall of the adhesive storage part 51.

[0047] The interval between the pressing parts 50a on the two columns is such that parts of the two pressing parts 50a abut on both ends of the horizontal direction in the cross section of the tube 22. Since the abutting parts of the two pressing parts 50a are formed at the same distance from the opening, the tube 22 in the abutting state at two points is arranged parallel to the optical fiber 20. Since the tube 22 is pressed at two points, it is possible to prevent the tube 22 from tilting, which has the advantage that the tube 22 can be arranged parallel to the optical fiber 20. Therefore, it is possible to prevent the tube 22 from contacting the optical fiber 20. The two pressing parts 50a have the same width Wa, but may have different widths from each other. In addition, the two pressing parts 50a are arranged so that the center of the interval between the two pressing parts 50a is the center of the opening of the optical fiber coupling part protection part 31. However, as long as a part of the tube 22 is in a position where it abuts against at least one of the two pressing parts 50a, the center of the distance between the two pressing parts 50a does not have to be the center of the opening of the optical fiber coupling part protection part 31. In addition, in this embodiment 2, a connecting part is provided between the two pressing parts 50a, but the shape and size of the connecting part are not limited to a rectangle as long as it does not come into contact with the optical fiber 20. There is no need to have a connecting part, but if there is a risk of the dropped adhesive spreading, it is necessary to increase the depth of the adhesive storage part 51.

[0048] The tips 50BS of the two pressing parts 50a are located near the lower side (the side closer to the optical fiber 20) of the tube 22, and the lower surface (the surface not in contact with 31a) of the connecting part has a thickness approximately equal to the opening H1. (An example of the present embodiment 2 is as follows. The thickness H1 of the opening of the side portion 31c (the thickness from the upper surface 31TS of the optical fiber coupling portion protection portion 31 to the position 31cBS of the opening) is 0.9 mm, and the thickness H3a from the upper surface 31TS to the tip 50aBS of the pressing portion 50a is 1.8 mm. The distance between the two pressing portions 50a is appropriately set to be approximately between the inner diameter and the outer diameter of the tube 22 (approximately 0.82 mm to 0.9 mm). This is because the tube 22 is elliptical in shape and therefore stretches slightly in the left-right direction. Therefore, in the structure of the present embodiment 2, as shown in FIG. 7, when the tube 22 is inserted into the opening of the side portion 31c, both sides of the tube 22 abut against the two pressing portions 50a at the same time and stop. Meanwhile, the optical fiber 20 inserted into the hollow portion of the tube 22 can pass between the two pressing portions 50a. In this manner, optical coupling can be achieved between the end face of the fiber block 21 fixed to the tip of the optical fiber 20 and the end face of the silicon chip 23.

[0049] This embodiment 2 has the same effect as embodiment 1, but the adhesive storage section of this embodiment 2 has an additional advantage that, by abutting the tube 22 against two pressing portions 50a, the tube 22 can be positioned parallel to the optical fiber 20 in the abutment process, and the pressing process can be carried out more easily, accurately, and reliably than in the case of abutment at one point.

[0050] Example 3 With reference to Fig. 8, a third embodiment, which is a modification of the second embodiment, will be described. Fig. 8(a) is a schematic plan view of the underside of a portion of the optical fiber coupling protection portion 31. Fig. 8(b) is a cross-sectional view of a portion of the optical fiber coupling protection portion 31 taken along the VIIIb-VIIIb cross-sectional line. Fig. 8(c) is a cross-sectional view taken along the VIIIc-VIIIc cross-sectional line. As shown in Fig. 8, an L-shaped or hook-shaped pressing portion may also be used. A columnar central portion approximately perpendicular to the upper portion 31a may serve as the pressing portion 50a, and a portion approximately horizontal to the upper portion 31a may form a portion of the adhesive containing portion 51.

[0051] (Other variations) In the first embodiment of FIG. 6, the tip 50BS of the pressing part 50 is shown as a rectangle, but the pressing part 50 may have a shape surrounding the opening. In this case, the shape may be such that the adhesive that falls falls into the adhesive storage part 51, and there is no risk of the fallen adhesive spreading. In the first embodiment of FIG. 6, the width of the pressing part 50a is made wider than the outer diameter of the tube 22, so that the spreading of the falling adhesive can be prevented. As a modification of this example, the width of the pressing part 50 may be expanded to the side part 31b to enhance the role of preventing the spreading of the falling adhesive. In this case, the expanding part may have a flat or curved shape, and the angle between the center part (part of width W) and the expanding part is from 90 degrees to 180 degrees to prevent the spreading of the falling adhesive. In addition, as a modification of FIG. 7 and FIG. 8, the width of the columnar pressing part 50a may be expanded to the side part 31b to enhance the role of preventing the spreading of the falling adhesive. In this case, the expanding portion may be flat or curved, and the angle between the columnar pressing portion 50a (part with width Wa) and the expanding portion can be between 90 degrees and 180 degrees to prevent the fallen adhesive from spreading. [Explanation of symbols]

[0052] 100 Optical Module (COSA) 10 Device Substrate 20 Optical Fiber 21 Fiber Block 22 Tube 23 Silicon chip 24 Fiber protection resin 30 Lid 31 Optical fiber joint protection section 31a Upper 31b Side 31c Side portion having an opening 32a upper part 32b Side 40 Adhesive 40a, 40b fillet 50, 50a Pressing part 51 Adhesive storage section

Claims

1. A part used for connecting a silicon chip integrated on a device substrate and an optical fiber, a flat top portion and a first side portion and a second side portion substantially perpendicular to the top portion; a recess defined by the top, the first side, and the second side; a pressing portion formed at a predetermined position of the upper portion in the recess and substantially perpendicular to the upper portion; Parts equipped with.

2. the component further comprises a tube having a hollow portion through which the optical fiber passes, the tube being placed in the opening of the second side portion; The component according to claim 1 , wherein the pressing portion is formed at a position where a part of the tube abuts against the pressing portion but does not contact the optical fiber.

3. The component according to claim 2 , wherein the pressing portion is formed to abut against a portion of the tube at one point.

4. The component according to claim 2 , wherein the pressing portion is formed so as to abut against a portion of the tube at two points.

5. The component according to claim 4 , wherein the pressing portion that abuts against a portion of the tube at the two locations is connected at the upper side.

6. The component of claim 2 , further comprising an adhesive receiving portion formed between the pressing portion and the opening.

7. The component according to claim 6 , wherein the adhesive-receiving portion is formed by cutting further than a surface on which the pressing portion is formed.

8. An optical module comprising a component according to any one of claims 1 to 7, The device substrate; a waveguide formed on the surface of the silicon chip; Equipped with an optical module, wherein the waveguide and the optical fiber are optically coupled at an end face of the silicon chip;

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