JP2000131558A - Optical module and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an optical module which is low in cost and highly reliable by subjecting the optical coupling part of the optical element of the optical module and the optical waveguide of the optical element to end-sealing with a translucent resin and enclosing the entire part of the module with a molded resin. SOLUTION: The ends of the optical element 12 and the optical waveguide 10 are end-sealed with a silicone resin 20. Feed patterns 14 and 16 and a lead 4a formed on a substrate 6 are connected by a gold wire 22. A lead frame 4, the substrate 6, the optical waveguide 10, the optical element 12 and the silicone resin 20 exclusive of part of the lead 4a are covered by the molded epoxy resin 24. The epoxy resin 24 delineates a guide hole 26 for guiding a ferrule 28 to be inserted arriving at the other end of the optical waveguide 10. Then, the optical fiber inserted into the ferrule 28 is eventually efficiently optically coupled to the optical waveguide 10 in the state that the ferrule 28 is inserted into the guide hole 26 until the ferrule 28 comes into contact with the end of the substrate 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an optical module and a method for manufacturing the same. In recent years, optical access networks have been actively developed. For realizing an optical access network, cost reduction of an optical device and / or an optical module is a very important issue.

2. Description of the Related Art Light-to-electric conversion or electric-
Further cost reduction is required for sealing an optical element for performing light conversion, and there is a demand for an optical module that can easily seal an optical element and secure sufficient reliability.

[0003]

2. Description of the Related Art At present, many optical modules use a metal package or a ceramic package in order to ensure reliability and hermetically seal the inside of the package by welding or soldering. It will be expensive. In order to reduce the cost of the optical module, simplification of the sealing method of the optical element has become an important issue.

As an example of simplification for hermetically sealing an optical module, a method has been proposed in which a resin is applied to the entire surface of a substrate on which an optical element is mounted, and the resin is cured to perform hermetic sealing (Mitsuo Fukuda). et al., “Plastic Packaging of S
emiconductor Laser Diode ”, Electriconic Component
s and Conference, 1996, pp1101-1108).

[0005]

As described in the above-mentioned document, a resin is applied to the entire surface of a substrate on which an optical element is mounted, and the resin is cured to form a hermetic seal. The difference in the coefficient of linear expansion between the resin and the resin is large, and the resin may be peeled off, cracked, or the like, or the substrate may be broken by the residual stress of the resin.

Further, in an optical module such as a light emitting module or a light receiving module, a connection with an optical connector is required to send an optical signal to an optical fiber transmission line or to receive an optical signal from the optical fiber transmission line. Although necessary, there is a need for an optical module that allows connection with an optical connector with a simple structure.

It is therefore an object of the present invention to provide a low-cost and highly reliable optical module. Another object of the present invention is to provide a method for manufacturing an optical module with low cost and high reliability.

[0008]

According to one aspect of the present invention, a lead frame having a plurality of leads, a substrate having a plurality of conductive patterns mounted on the lead frame, and a substrate formed on the substrate. An optical element for converting between light and electricity mounted on the substrate so as to be optically coupled to one end of the optical waveguide, and a light-transmitting first element for sealing the optical element. Resin, a wire connecting the conductive pattern and the lead, and a second molded part surrounding the substrate, the optical element, the translucent first resin, the wire and the lead frame except for a part of the lead. An optical module, comprising: a resin; and the second resin defines a guide hole for a ferrule guide to be inserted, which reaches the other end of the optical waveguide.

According to another aspect of the present invention, a lead frame having a plurality of leads, a substrate having a plurality of conductive patterns mounted on the lead frame, an optical waveguide formed on the substrate, An optical element mounted on the substrate for converting between light and electricity so as to be optically coupled to one end of the optical waveguide; a sleeve having a first end adjacent to the other end of the optical waveguide; The substrate, the optical element, the sleeve, and the light-transmitting first resin for sealing the optical element, a wire connecting the conductive pattern and the lead, and a part of the sleeve and the lead. An optical module comprising a first resin, a wire, and a molded second resin surrounding the lead frame is provided.

In the optical module of the present invention, since the entire module including the substrate is sealed with the molded second resin, the molding resin does not peel off from the substrate, and cracks and the like do not occur in the molding resin. The cost of the optical module can be reduced and its reliability can be ensured.

According to still another aspect of the present invention, there is provided a method of manufacturing an optical module, comprising: providing a lead frame having a plurality of leads; and forming an optical waveguide having first and second ends on the lead frame. A substrate having a conductive pattern is mounted, and an optical element for converting between light and electricity is mounted on the substrate so as to be optically coupled to the first end of the optical waveguide. Applying a resin on the optical element, curing the light-transmitting first resin, sealing the optical element and the first end of the optical waveguide with the light-transmitting first resin, And the lead are connected by a wire, and except for a part of the lead, a mold having an opening in a side wall surrounding the substrate, the optical element, the transparent first resin, the wire and the lead frame is provided, Through the opening to the end face of the substrate Insert the core until the method of manufacturing an optical module, wherein the curing by injecting a second resin into said mold is provided.

According to still another aspect of the present invention, there is provided a method for manufacturing an optical module, comprising: providing a lead frame having a plurality of leads; and forming an optical waveguide having first and second ends on the lead frame. A substrate having a conductive pattern is mounted, and an optical element for converting between light and electricity is mounted on the substrate so as to be optically coupled to the first end of the optical waveguide. Applying a resin on the optical element, curing the light-transmitting first resin, sealing the optical element and the first end of the optical waveguide with the light-transmitting first resin, And the lead are connected by a wire, except for a part of the lead, and a mold having an opening in a side wall surrounding the substrate, the optical element, the transparent first resin, the wire and the lead frame is provided, and the tip is the Front so as to be adjacent to the second end of the optical waveguide Insert the sleeve through the opening,
There is provided a method for manufacturing an optical module, wherein a core is inserted into the sleeve until a leading end contacts an end of the substrate, and a second resin is injected into the mold and cured.

As an alternative, a resin package having an open top may be used instead of the mold, and a second resin may be injected into the resin package and cured so as to be integrated with the resin package. In this case, mold
Is unnecessary.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A number of embodiments of the present invention will be described below with reference to the drawings. In the description of each embodiment, substantially the same components are denoted by the same reference numerals.

Referring to FIG. 1, there is shown a sectional view of an optical module 2A according to a first preferred embodiment of the present invention. Reference numeral 4 denotes a lead frame having a plurality of leads 4a, and a silicon substrate 6 is fixed on the lead frame 4 by bonding or the like.

The silicon substrate 6 has a step 8 as shown in FIG.
, And an optical waveguide 10 is further formed. An optical element 12 such as a laser diode or a photodiode for converting between light and electricity is mounted on the silicon substrate 6 so as to be optically coupled to one end of the optical waveguide 10.

On the substrate 6, a pair of power supply patterns 1 is further provided.
4, 16 are formed. The power supply pattern 14 is connected to the optical element 12 via the gold wire 18, and the power supply pattern 16 is directly connected to the optical element 12.

The ends of the optical element 12 and the optical waveguide 10 are sealed with a silicone resin 20. The silicone resin 20 is transparent to an optical signal transmitted or received by the optical element 12.

The power supply patterns 14 formed on the substrate 6
The lead 16 and the lead 4a are connected by a gold wire 22. Leaving a part of the lead 4a, the lead frame 4,
The substrate 6, the optical waveguide 10, the optical element 12, and the silicone resin 20 are covered with a molded epoxy resin 24.

The epoxy resin 24 is inserted into the guide hole 2 for guiding the ferrule 28 to reach the other end of the optical waveguide 10.
6 is defined. Therefore, when the ferrule 28 is inserted into the guide hole 26 until the ferrule 28 contacts the end of the substrate 6, the optical fiber inserted into the ferrule 28 is efficiently optically coupled to the optical waveguide 10.

In the optical module 2A of this embodiment, the ends of the optical element 12 and the optical waveguide 10 are sealed with a translucent silicone resin 20, and the whole is covered with a molded epoxy resin 24. An inexpensive and highly reliable optical module can be provided.

Next, a method of manufacturing the optical module 2A of the first embodiment will be schematically described. First, a lead frame 4 having a plurality of leads 4a is provided, and a silicon substrate 6 having an optical waveguide 10 having first and second ends and a plurality of conductive patterns 14 and 16 is mounted on the lead frame 4. On the silicon substrate 6, the first
An optical element 12 for converting between light and electricity is mounted so as to be optically coupled to the end.

Next, the silicone resin 20 is applied to the optical element 12.
The silicone resin 20 is dropped at about 150 ° C to 16 ° C.
Cured by heating to 0 ° C, silicone resin 2 of convex shape
0 seals the optical element 12 and one end of the optical waveguide 10. Next, the power supply patterns 14, 16 on the substrate 6, the leads 4a, and the gold wires 22 are connected by bonding.

Next, a mold having an opening in a side wall surrounding the substrate 6, the optical element 12, the silicone resin 20, the wires 22, and the lead frame 4 except for a part of the leads 4a is set. The core is inserted through the opening of the mold until it comes into contact with the end face of the substrate 6, and the epoxy resin 24 is injected into the mold from the injection port of the mold.

After the injection of the epoxy resin into the mold is completed, the epoxy resin is heated to about 150 ° C. to 160 ° C. to be cured. After the epoxy resin has hardened, the mold is released and the core is pulled out, so that the guide holes 2 defined in the molded epoxy resin 24 as shown in FIG.
6 can be obtained.

Referring to FIG. 3, there is shown a sectional view of an optical module 2B according to a second preferred embodiment of the present invention. The optical module 2B of the present embodiment is similar to the optical module 2A of the first embodiment shown in FIG.
The only difference from the optical module 2A of the first embodiment shown in FIG.

The second substrate 30 is also preferably a silicon substrate, and is bonded to the lead frame 4. In the optical module 2B of the present embodiment, the guide hole 26 is defined by the epoxy resin 24 and the V groove 32 of the second substrate 30.

Referring to FIG. 5, there is shown a sectional view of an optical module 2C according to a third preferred embodiment of the present invention. The optical module 2C of the present embodiment is similar to the optical module 2A of the first embodiment shown in FIG. 1, except that the lid 34 having a V-groove is adhered to the substrate 6 only in the first embodiment shown in FIG. It is different from the optical module 2A of the embodiment.

In the optical module 2C of the present embodiment, FIG.
The guide hole 26 is defined by the epoxy resin 24 and the V-shaped groove of the lid 34, similarly to the optical module 2B of the second embodiment shown in FIG.

Referring to FIG. 6, there is shown a sectional view of an optical module 2D according to a fourth preferred embodiment of the present invention. The optical module 2D of the present embodiment employs both the second substrate 30 of the second embodiment and the lid 34 of the third embodiment. Therefore, the guide hole 26 is formed between the epoxy resin 24 and the second substrate 30.
And the V-groove of the lid 34.

Referring to FIG. 7, there is shown a sectional view of an optical module 2E according to a fifth preferred embodiment of the present invention. In this embodiment, a sleeve 36 is used to define a guide hole for the ferrule 28. The sleeve 36 has one end arranged adjacent to the end of the optical waveguide 10.

The manufacturing method of the optical module 2E of the present embodiment is the same as that of the first embodiment described above, except for the following points. That is, in the above-described first embodiment, the core is inserted into the opening of the mold side wall, but in the present embodiment, the sleeve 36 is inserted into the opening, and then the core is inserted into the sleeve 36. Is injected and cured.

Referring to FIG. 8, there is shown a sectional view of an optical module 2F according to a sixth preferred embodiment of the present invention. The optical module 2F of the present embodiment is similar to the optical module 2E of the fifth embodiment shown in FIG.
The only difference is that 0 is used. The sleeve 36 is partially inserted and supported in the V groove of the second substrate 30.

Referring to FIG. 9, there is shown a sectional view of an optical module 2G according to a seventh embodiment of the present invention. The optical module 2G of this embodiment is similar to the optical module 2E of the fifth embodiment shown in FIG. 7, and differs only in that a lid 34 having a V-groove is used. The sleeve 36 is partially inserted into the V groove of the lid 34.

Referring to FIG. 10, there is shown a sectional view of an optical module 2H according to an eighth embodiment of the present invention. The optical module 2H of this embodiment is characterized in that a resin package 38 having an open top surface is used, and the epoxy resin 24 is injected into the resin package 38 and thermally cured.

The outline of the method of manufacturing the optical module 2H of the present embodiment is as follows. First, the lead frame 4 on which the substrate 6 on which the optical element 12 is mounted is mounted in a resin package 38 having an open top surface and an opening 40 on the side surface.
Is fixed by bonding or the like.

Next, the silicone resin 20 is applied to the optical element 12.
The silicone resin 20 is dropped at about 150 ° C to 16 ° C.
Heated to 0 ° C and thermally cured to form a convex silicone resin 2
0 seals the ends of the optical element 12 and the optical waveguide 10.

Further, the power supply pattern on the substrate 6 and the leads 4
a is bonded by a wire. Next, the sleeve 36 is inserted through the opening 40 of the resin package 38 until its tip is adjacent to the end of the substrate 6.

Further, the core is inserted into the sleeve 36 until the tip thereof contacts the end of the substrate 6, and the epoxy resin 24 is injected into the resin package 38 in this state. The epoxy resin is heated to about 150 ° C. to 160 ° C. to be thermally cured, and the thermally cured epoxy resin 24 and the resin package 38 are integrated.

Next, by pulling out the core from the sleeve 36, the ends of the optical element 12 and the optical waveguide 10 are sealed with the silicone resin 20, and the optical module 2H in which the resin package 38 and the epoxy resin 24 are integrated. Can be obtained.

Referring to FIG. 11, there is shown a sectional view of an optical module 2I according to a ninth embodiment of the present invention. The optical module 2I of the present embodiment is similar to the optical module 2H of the eighth embodiment shown in FIG. 10, and differs only in that a second substrate 30 having a V groove is used. The sleeve 36 is partially inserted and supported in the V groove of the second substrate 30.

Referring to FIG. 12, there is shown a sectional view of an optical module 2J according to a tenth embodiment of the present invention. The optical module 2J of the present embodiment is similar to the optical module 2H of the eighth embodiment shown in FIG.
The only difference is that No. 4 was used. The cover 34 is fixed to the substrate 6, and the sleeve 36 is partially inserted into the V groove of the cover 34.

Referring to FIG. 13, there is shown a perspective view of a connection structure between the optical module and the optical connector according to the present invention. For example, the concave portion 42 is formed integrally with the optical module 2A of the first embodiment when the epoxy resin 24 is molded.

Then, as shown in FIG.
4 is provided inside the housing 46 of the optical module 2A.
2 are formed. The optical connector 44 has a ferrule 48 connected to an optical fiber 50. In the ferrule 48, a bare fiber from which the coating of the optical fiber 50 is removed is inserted and fixed.

When the optical connector 44 is fitted to the optical module 2A, the ferrule 48 of the optical connector 44 is inserted into the guide hole 26 of the optical module 2A.
Of the optical connector 44 is engaged with the concave portion 42 of the optical module 2A in this state.

As described above, since the projection 52 of the optical connector 44 is engaged with the recess 42 of the optical module 2A, even if a certain tensile force is applied to the optical connector 44, the engagement between the optical connector 44 and the optical module 2A is achieved. Is prevented from coming off.

Referring to FIG. 15, there is shown a perspective view of another connection structure between the optical module and the optical connector. In this connection structure, the optical module 2A 'is provided with a convex portion 5 of epoxy resin.
4 is formed, and a hole 56 is formed in the housing 46 of the optical connector 44 'so as to be engaged with the projection 54 of the optical module 2A'.

As described above, the resin module 54 is formed on the optical module.
And the optical connector 44 'is formed with a hole 56 in which the projection 54 is engaged, and even when a certain amount of pulling force is applied to the optical connector 44'.
And the optical module 2A 'are not disengaged.

[0049]

According to the present invention, the optical element of the optical module and the optical coupling portion between the optical element and the optical waveguide are sealed with a translucent resin, and the entire module is surrounded by the molded resin. An optical module with high performance can be provided. Since the entire module is covered with the thermosetting resin, peeling of the resin from the substrate and cracking of the resin, which are problems in the related art, can be prevented.

[Brief description of the drawings]

FIG. 1 is a sectional view of an optical module according to a first embodiment of the present invention.

FIG. 2 is a perspective view of a substrate used in the first embodiment.

FIG. 3 is a sectional view of an optical module according to a second embodiment of the present invention.

FIG. 4 is a perspective view of a substrate having a V groove used in a second embodiment.

FIG. 5 is a sectional view of an optical module according to a third embodiment of the present invention.

FIG. 6 is a sectional view of an optical module according to a fourth embodiment of the present invention.

FIG. 7 is a sectional view of an optical module according to a fifth embodiment of the present invention.

FIG. 8 is a sectional view of an optical module according to a sixth embodiment of the present invention.

FIG. 9 is a sectional view of an optical module according to a seventh embodiment of the present invention.

FIG. 10 is a sectional view of an optical module according to an eighth embodiment of the present invention.

FIG. 11 is a sectional view of an optical module according to a ninth embodiment of the present invention.

FIG. 12 is a sectional view of an optical module according to a tenth embodiment of the present invention.

FIG. 13 is a diagram showing a connection structure between an optical module and an optical connector.

FIG. 14 is a perspective view of an optical connector used in the connection structure of FIG.

FIG. 15 is a diagram showing another connection structure of the optical module and the optical connector.

[Explanation of symbols]

 Reference Signs List 4 lead frame 4a lead 6 substrate 10 optical waveguide 12 optical element 20 sealing resin (silicone resin) 24 molding resin (epoxy resin) 26 guide hole 28 ferrule 36 sleeve 38 resin package

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Seimi Sasaki 4-1-1 Kamikadanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture Inside Fujitsu Limited (72) Inventor Naoki Yamamoto 4-chome, Kamiodanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture No. 1 Fujitsu Limited (72) Inventor Mitsuo Fukuda 3-19-2 Nishi-Shinjuku, Shinjuku-ku, Tokyo Nippon Telegraph and Telephone Corporation (72) Yasufumi Yamada 3-19 Nishi-Shinjuku, Shinjuku-ku, Tokyo No. 2 Nippon Telegraph and Telephone Corporation F-term (reference) 2H037 BA02 BA11 BA24 DA03 DA04 DA06 DA12 DA13 DA33 DA36 5F088 AA01 BA16 BA18 BB01 EA11 JA14 LA01

Claims (16)

[Claims] A lead frame having a plurality of leads; a substrate having a plurality of conductive patterns mounted on the lead frame; an optical waveguide formed on the substrate; and light at one end of the optical waveguide. An optical element mounted on the substrate for converting between light and electricity so as to be coupled; a light-transmitting first resin for sealing the optical element; and connecting the conductive pattern and the lead Excluding a part of the leads, the substrate, the optical element, the translucent first resin, and a molded second resin surrounding the wires and the lead frame; An optical module, wherein a guide hole for a ferrule guide to be inserted, which reaches the other end of the wave path, is defined. 2. The semiconductor device according to claim 1, further comprising: a second substrate having a V-shaped groove mounted on the lead frame; wherein the guide hole is defined by the V-shaped groove of the second resin and the second substrate.
An optical module as described. 3. A lid having a V-groove fixed to the substrate; wherein the guide hole is provided between the second resin and the V of the lid.
The optical module according to claim 1, wherein the optical module is defined by the groove. 4. The apparatus according to claim 1, further comprising a lid having a V-shaped groove fixed to the substrate; wherein the guide hole is provided between the second resin and the second resin.
3. The optical module according to claim 2, wherein the optical module is defined by a substrate and a V groove of the lid. 5. The optical module according to claim 1, wherein the translucent first resin is a silicone resin, and the second resin is an epoxy resin. 6. A lead frame having a plurality of leads; a substrate having a plurality of conductive patterns mounted on the lead frame; an optical waveguide formed on the substrate; and light at one end of the optical waveguide. An optical element for converting between light and electricity mounted on the substrate so as to be coupled; a sleeve having a first end adjacent to the other end of the optical waveguide; and a transparent sealing element for the optical element. An optical first resin; a wire connecting the conductive pattern and the lead;
Except for a part of the sleeve and the lead, the substrate,
An optical module, comprising: an optical element, a sleeve, a translucent first resin, a molded second resin surrounding a wire and a lead frame. 7. The light of claim 6, further comprising a second substrate having a V-groove mounted on the lead frame; wherein the sleeve is partially inserted into the V-groove of the second substrate. module. 8. The optical module according to claim 6, further comprising a lid having a V groove fixed to the substrate; wherein the sleeve is partially inserted into the V groove of the lid. 9. The optical module according to claim 6, wherein the first translucent resin is a silicone resin, and the second resin is an epoxy resin. 10. A resin package having an open upper surface;
A lead frame accommodated in the package such that a plurality of leads protrude from the package; a substrate having a plurality of conductive patterns mounted on the lead frame; first and second substrates formed on the substrate; An optical waveguide having a second end; an optical element for converting between light and electricity mounted on the substrate so as to be optically coupled to the first end of the optical waveguide; and the optical element and the optical waveguide A first resin that seals a first end of the optical waveguide; a sleeve having a first end adjacent to the second end of the optical waveguide and a second end protruding from the package; the conductive pattern and the lead And a second resin molded in the package. 11. A V mounted on the lead frame.
11. The device of claim 10, further comprising a second substrate having a groove; wherein the sleeve is partially inserted into a V-groove of the second substrate.
An optical module as described. 12. The optical module according to claim 10, further comprising a lid having a V groove fixed to the substrate; wherein the sleeve is partially inserted into the V groove of the lid. 13. The light-transmissive first resin is a silicone resin, and the second resin is an epoxy resin.
An optical module as described. 14. A method of manufacturing an optical module, comprising: providing a lead frame having a plurality of leads; and a substrate having an optical waveguide having first and second ends and a plurality of conductive patterns on the lead frame. Mounting an optical element for converting between light and electricity on the substrate so as to be optically coupled to the first end of the optical waveguide; applying a translucent first resin on the optical element Curing the light-transmitting first resin and sealing the optical element and the first end of the optical waveguide with the light-transmitting first resin; connecting the conductive pattern and the lead with a wire A mold having an opening in a side wall surrounding the substrate, the optical element, the light-transmitting first resin, the wires and the lead frame except for a part of the lead; and contacting the end face of the substrate through the opening of the mold. Insert core until touching; before Method of manufacturing an optical module, characterized in that; cured by injecting the second resin into a mold. 15. A method of manufacturing an optical module, comprising: providing a lead frame having a plurality of leads; and a substrate having an optical waveguide having first and second ends and a plurality of conductive patterns on the lead frame. Mounting an optical element for converting between light and electricity on the substrate so as to be optically coupled to the first end of the optical waveguide; applying a translucent first resin on the optical element Curing the light-transmitting first resin and sealing the optical element and the first end of the optical waveguide with the light-transmitting first resin; connecting the conductive pattern and the lead with a wire Excluding a part of the lead, providing a mold having an opening in a side wall surrounding the substrate, the optical element, the first translucent resin, the wire, and the lead frame; a tip is adjacent to a second end of the optical waveguide; Insert the sleeve through the opening so that Teeth; method of manufacturing an optical module, characterized in that; cured by injecting the second resin into said mold; inserting the core into the sleeve to the tip abuts on an end of the substrate. 16. A method of manufacturing an optical module, comprising: providing a resin package having an open top surface and an opening on a side surface; and accommodating a lead frame in the package so that a plurality of leads protrude from the package; A substrate having an optical waveguide having first and second ends and a plurality of conductive patterns is mounted on the lead frame; light is applied to the substrate so as to optically couple to the first end of the optical waveguide. Mounting an optical element for converting between electricity; applying a light-transmitting first resin onto the optical element; curing the light-transmitting first resin to form a first light-transmitting resin and a light-transmitting first resin. Sealing the end with the translucent first resin; connecting the conductive pattern and the lead with a wire; and passing the sleeve through the opening of the package so that the tip is adjacent to the second end of the optical waveguide. Insert; tip forward Method of manufacturing an optical module, characterized in that; cured by injecting the second resin into said package; inserting the core into the sleeve until abutting the edge of the substrate.