JPH06350113A - Mounting structure of light semiconductor module - Google Patents

Abstract

(57) [Summary] [Object] A mounting structure of a semiconductor module in which an optical semiconductor element and an optical fiber are optically coupled to each other, and an object thereof is to reduce the size and cost of an optical device. [Structure] A semiconductor module 30 in which an optical semiconductor element and an optical fiber 8 are optically coupled in a package 31,
A pair of guide grooves 35 formed opposite to the side surface 32 of the package 31 and having a groove width parallel to the axis of the optical fiber 8 which is slightly larger than the board thickness of the mother board 40 and the end surface 33 of the package 31. Leads 51, rectangular notches 41 provided on the mother board 40 so that one side edge side is open, the width is desirably smaller than the width of the package 31, and the length is approximately equal to the length of the package 31, and the respective leads 51. Pads arranged near the inner edge of the square cut 41 to connect the tip
42 and 42.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical semiconductor module mounting structure in which an optical semiconductor element and an optical fiber are optically coupled.

[0002]

2. Description of the Related Art FIG. 4 is a conventional view, (A) is a sectional view, and (B) is a sectional view.
Is a side section showing the mounting structure. In the figure, 1 is an optical semiconductor element such as a semiconductor laser or a light receiving element, and 8 is an optical fiber optically coupled with the optical semiconductor element 1.

Reference numeral 10 denotes an optical semiconductor module in which the optical semiconductor element 1 and the optical fiber 8 are optically coupled. More specifically, the optical semiconductor module 10 is assembled such that the optical semiconductor assembly, the lens assembly, and the optical fiber assembly are optically coupled, and is integrally fixed.

The optical semiconductor assembly is a stem member in which a substantially rectangular plate-shaped flange portion 5 is provided on the outer peripheral portion of a substantially disk-shaped stem 4 made of a metal material such as Fe-Ni-Co alloy (trade name: Kovar). The carrier 2 is fixed to the end surface of the stem 4, and the optical semiconductor element 1 is mounted on the carrier 2 by soldering.

Then, the lead 3 is hermetically sealed to penetrate the stem 4, and the lead 3 of the optical semiconductor element 1 is led out from the end face opposite to the optical fiber 8. The lens assembly includes a bottomed cylindrical lens holder 7 and a lens 6 inserted into a shaft center hole of a bottom end surface of the lens holder 7.

Numeral 9 is a cylindrical ferrule in which the end of the optical fiber 8 is inserted into the pore of the axial center and the outer periphery of the optical fiber 8 is fixed to the inner wall of the pore with an adhesive. 9A is
It is a cylindrical ferrule holder 9A having a flange with an outer diameter equal to the outer diameter dimension of the lens holder 7. An optical fiber assembly is constructed by inserting the ferrule 9 into the hollow hole of the ferrule holder 9A.

The optical fiber assembly protects the lead-out portion of the optical fiber 8 by covering the ferrule holder 9A with a rubber bush on the side opposite to the flange. The optical semiconductor module 10 described above is integrated by fixing the lens assembly to the optical semiconductor assembly and then fixing the optical fiber assembly to the lens assembly.

More specifically, the lens holder 7 is inserted by inserting the opening side of the lens holder 7 into the outer periphery of the circular projecting plate portion of the stem 4.
The optical axis of the optical semiconductor element 1 and the optical axis of the lens 6 are made to coincide with each other by soldering the end face of the to the stem 4.

The lens 6 is moved and adjusted in the optical axis direction within the axial center hole of the lens holder 7 so that the optical coupling between the optical semiconductor element 1 and the lens 6 is maximized. Further, the end surface of the ferrule holder 9A and the end surface of the lens holder 7 on the lens 6 side are fixed by soldering.

Reference numeral 20 is a printed wiring board on which desired components are mounted and a drive circuit (when the optical semiconductor element is a semiconductor laser) or an amplifier circuit (when the optical semiconductor element is a light receiving element) is provided.

Reference numeral 21 denotes a case made of a metal material and having a shallow box shape with an open upper part, and a case 21 in which an optical semiconductor module 10 is mounted on a side wall 21A thereof and a printed wiring board 20 is horizontally accommodated and held therein.

Reference numeral 25 is a mother board which is inserted in parallel with a shelf (not shown). I / O terminals 24 that penetrate (insulate through) the bottom plate of this case 21 are provided.
The upper end portion of is inserted into the through hole of the printed wiring board 20 and soldered.

On the other hand, in the optical semiconductor module 10, the flange portion 5 is brought into contact with the outer side surface of the side wall 21A of the case, and is fixed to the case 21 with screws. Each lead 3 of the optical semiconductor module 10 is soldered to a corresponding pad provided on the surface of the printed wiring board 20.

After the optical semiconductor module 10 and the printed wiring board 20 are assembled, the case 21 is closed with a lid. The case 21 incorporating the optical semiconductor module 10 and the printed wiring board 20 in this way is placed on the motherboard 25, and the lower ends of the input / output terminals 24 are inserted into the corresponding through holes of the motherboard 25 and soldered. It is mounted on the motherboard 25.

[0015]

By the way, the conventional optical semiconductor module provided with the stem member in which the flange portion which is long in the left-right direction and the disc-shaped stem are integrated as described above is a problem. There is a problem in that it requires a case much larger than a printed wiring board for wearing, which increases the cost.

Further, since the optical semiconductor module and the case are mounted on one side of the mother board, the mounting height increases accordingly. Therefore, in an optical device configured by mounting a plurality of motherboards in parallel, the distance between the motherboards becomes large, and the optical device becomes large.

Also, since the leads are routed to the upper surface of the printed wiring board housed and fixed in the case and soldered to the pads on the upper surface after the optical semiconductor module is mounted on the case, the connecting work is troublesome and time consuming. There was a problem.

The present invention was created in view of the above points, and an object thereof is to provide an optical semiconductor module mounting structure which promotes miniaturization of an optical device and is low in cost.

[0019]

To achieve the above object, the present invention provides an optical semiconductor in which an optical semiconductor element and an optical fiber 8 are optically coupled in a package 31, as illustrated in FIG. Module 30, side 32 of package 31
A pair of guide grooves 35 formed facing each other and having a groove width parallel to the axis of the optical fiber 8 slightly larger than the plate thickness of the mother board 40; and leads 51 led out from the end surface 33 of the package 31; In order to connect the tip end of each lead 51 to a rectangular notch 41 provided on the mother board 40 with one side edge opening and having a width smaller than the width of the package 31 and a length substantially equal to the length of the package 31. , Square notch 41
The pads 42 arranged on the motherboard 40 near the inner edge of the
And the guide groove 35 is inserted into and engaged with the rectangular cut 41, and the optical semiconductor module 30 is mounted on the motherboard 40.

Further, as illustrated in FIG. 3, the package 31
An optical semiconductor module 30 in which an optical semiconductor element and an optical fiber 8 are optically coupled to each other, which is a side surface 32 of a package 31.
A pair of guide grooves 35 having a groove width parallel to the axial center of the optical fiber 8 which is slightly larger than the board thickness of the mother board 40, and a plate-shaped lead terminal 55 led out from the side surface 32 of the package 31. The rectangular notch 41 is provided on the mother board 40 so that one side edge side is open, and the width thereof is smaller than the width of the package 31 and is substantially equal to the length of the package 31.
And the mother board 40 near the longitudinal side edge of the rectangular notch 41 in order to connect the tip ends of the respective plate-shaped lead terminals 55.
With the pad 45 disposed above, the guide groove 35 is inserted into and engaged with the rectangular cut 41, and the optical semiconductor module 30 is mounted on the mother board 40.

Alternatively, as illustrated in FIG. 2, a substrate 38 sealed in a package 31 and having a preamplifier 39 formed thereon,
An optical semiconductor element 1 which is a light receiving element mounted on the substrate 38,
The board 38 for connecting one end of the lead 51 or the plate-like lead terminal
And a pad disposed on the.

[0022]

The present invention has a mounting height that is divided into two equal parts on both left and right sides of a mother board provided with a drive circuit or an amplifier circuit.
The optical semiconductor module is directly mounted.

Therefore, as the mounting height of the optical semiconductor module mounted on the mother board becomes low, the present invention can be applied to an optical device constituted by mounting a plurality of mother boards in parallel to reduce the distance between the mother boards. , Miniaturization of optical devices is promoted.

Further, unlike the conventional example, the present invention does not require a printed wiring board different from the mother board and a case for accommodating the printed wiring board. Therefore, the cost is reduced by the printed wiring board and the case.

Further, the mounting work is completed only by inserting the guide groove provided in the package into the rectangular cut and connecting the lead of the optical semiconductor module and the pad of the motherboard in the open space. Therefore, the mounting work is short and easy.

On the other hand, according to the third aspect of the invention, since the preamplifier is sealed in the package and shielded, the cost is lower than that in which the preamplifier is provided on the motherboard and the preamplifier is partially shielded. become.

[0027]

The present invention will be described in detail with reference to the drawings. The same reference numerals denote the same objects throughout the drawings.

FIG. 1 is a perspective view of an embodiment of the present invention, FIG. 2 is a side sectional view of the embodiment of the present invention, and FIG. 3 is a perspective view of another embodiment of the present invention. In the figure, 30 is an optical semiconductor module in which an optical semiconductor element (light emitting element or light receiving element) 1 and an optical fiber 8 are optically coupled via a lens 6.

Reference numeral 31 is a rectangular package which is long in the axial direction of the optical fiber 8 made of a metal material and which is used to assemble and seal the optical semiconductor module 30. Also, the optical fiber 8 of the package 31
The lead 51 is led out from the end surface 33 opposite to the end surface from which the lead is drawn.

The package 31 is not limited to the rectangular shape and may be a cylindrical shape. Reference numeral 35 denotes a pair of guide grooves that are provided so as to face the pair of side surfaces 32 of the package 31 and that are parallel to the axis of the optical fiber 8. The groove width of the guide groove 35 is slightly larger than the board thickness of the mother board 40.

Reference numeral 40 is a mother board on which a drive circuit or an amplifier circuit and other circuits are formed. Then, the plurality of motherboards 40 are mounted in parallel on a shelf (not shown) to form an optical device.

The mother board 40 is provided with a rectangular notch 41 having a width which is desirably smaller than the width of the package 31 and a length which is substantially equal to the length of the package 31 so that one selected side edge is opened.

In addition, on the upper and lower surfaces of the mother board 40 or on one surface thereof, the leads are provided near the rear side edge of the rectangular notch 41.
Pads 42 to which the tip ends of 51 are connected by soldering are provided, and a pattern 43 is derived from each pad 42.

Further, along the opposing side edges of the rectangular cut 41 in the longitudinal direction, the fixing pads 44 each having an elongated rectangular shape are formed.
Is provided. To mount the optical semiconductor module 30 as described above on the mother board 40, first, the optical fiber 8 is placed on the front side, the guide groove 35 is engaged with the longitudinal side edge of the rectangular cut 41, and the package 31 is cut. The end face 33 is brought into contact with the inner bottom edge of the rectangular cut 41.

The tip of the lead 51 is connected to the corresponding pad 42.
Solder and connect to. Next, the fixing pad 44 and the package
The side surface 32 of 31 is soldered and fixed.

It is not always necessary to provide the fixing pad 44 on the mother board 40 and fix the side surface 32 of the package 31 by soldering. However, it is preferable to fix the fixing pad and the package from the viewpoint of preventing the package 31 from coming out of the rectangular notch 41 due to vibration or the like and damaging the leads 51 due to this.

As described above, the printed wiring board (printed wiring board 20 shown in FIG. 4) other than the mother board 40 and the case 21 for accommodating the printed wiring board 20 are not required. The cost is reduced by the case.

Further, since the mounting height of the optical semiconductor module mounted on the mother board becomes low, the optical device for mounting a plurality of mother boards in parallel becomes compact. Furthermore, the mounting work is completed simply by inserting the guide groove provided in the package into the rectangular notch and connecting the leads of the optical semiconductor module to the motherboard in the open space. .

The structure of the optical semiconductor module 30 is shown in FIG.
Will be described in detail with reference to. In FIG. 2, 6A is a lens holder made of a bottomed cylindrical metal material or the like.
The lens 6 is inserted and fixed in an axial hole that penetrates the bottom plate of 6A.

Reference numeral 9 denotes a cylindrical ferrule which is inserted and fixed in the hollow hole of the lens holder 6A. The end of the optical fiber 8 is inserted into the pore of the axial center of the ferrule, and the outer periphery of the optical fiber 8 is finely bonded with an adhesive. The inner surface of the ferrule 9 is fixed to the inner wall of the optical fiber 8 and finished by polishing so that the end surface of the ferrule 9 and the end surface of the optical fiber 8 match.

The ferrule 9 is pushed into the hollow hole of the lens holder 6A, and the ferrule 9 is fixed to the lens holder 6A so that the optical fiber 8 and the lens 6 are optically coupled with each other as desired. The package 31 has one end formed on the end face 33,
The other end has a hole 37 with a circular cross section into which the lens holder 6A is fitted and inserted, and a concave portion opened upward between the end face 33 and the hole 37.
36 are provided.

Lens holder 6A with the ferrule 9 inserted
The optical fiber 8 is fixed to the package 31 by press-fitting the optical fiber 8 into the hole 37 of the package 31 with the lens 6 side facing the concave portion 36 side.
Reference numeral 38 denotes a substrate fixed to the bottom plate 31A of the recess 36 so as to be in close contact therewith.

The optical semiconductor element 1 is mounted on the side edge of the substrate 38 on the lens 6 side so that the optical axis thereof coincides with the optical axis of the optical fiber 8. At this time, when the optical semiconductor element 1 is a light emitting element, the light emitted from the optical semiconductor element is condensed by the lens 6 on the incident end face of the optical fiber 8 and transmitted to the optical fiber 8, and when the optical semiconductor element 1 is a light receiving element. Needless to say, the lens 6 is fixed at a position where the light transmitted through the optical fiber 8 is focused on the light receiving surface of the optical semiconductor element by the lens 6.

Then, the lead 3 is hermetically sealed or the like to penetrate the end face 33, and the end inside thereof is connected to the input / output pattern of the substrate 38 by soldering or the like, and the opening of the concave portion 36 is covered with the lid 34 of the metal plate. The optical semiconductor element 1 and the substrate 38 are hermetically sealed.

When the optical semiconductor element 1 is a light receiving element, it is preferable to form a preamplifier 39 on the surface of the substrate 38 to amplify a minute photocurrent of the light receiving element. As mentioned above,
When the preamplifier 39 is formed on the substrate 38, the preamplifier 39 is shielded, so that almost no noise occurs in the output taken out from the lead 51.

The optical semiconductor module shown in FIG. 3 differs from the optical semiconductor module shown in FIG. 1 in that the leads are led out from the side surface of the package. In FIG. 3, reference numeral 55 indicates that each of the side walls of the package 31 faces each other.
It is a plate-shaped lead terminal fixed to the side wall by a hermetic seal or the like.

Package of each plate lead terminal 55
The inner tip of 31 is soldered and connected to the pads formed at the terminals of the input / output pattern of the substrate on which the optical semiconductor element is mounted.

Further, the mother board 40 has a rectangular notch 41.
Pads 45 are arranged and formed near the two side edges in the longitudinal direction. Then, the patterns 43 are derived from the pads 45, respectively.

In the optical semiconductor module 30 as described above, with the optical fiber 8 on the front side, the guide groove 35 is engaged with the longitudinal side edge of the rectangular notch 41 and is inserted into the rectangular notch 41, and the end surface of the package is rectangular. The plate-shaped lead terminals 55 projecting from the side surface 32 are located on the corresponding pads 45 in a state of being in contact with the bottom edge of the notch 41, and the pads 45 and the plate-shaped lead terminals 55 are soldered and connected.

In such an optical semiconductor module 30, the plate-shaped lead terminal 55 has a large width and a large rigidity. Pad again
The soldering area with 45 is wide, so the soldering strength is sufficiently large.

Therefore, as shown in FIG. 1, even if the package 31 and the mother board 40 are not specially soldered, the package 31 does not come out of the rectangular notch 41.

[0052]

As described above, according to the present invention, the guide grooves are provided on both side surfaces of the package, the package is inserted into the rectangular notch, and the optical semiconductor module is mounted on the motherboard. As the mounting height of the mounted optical semiconductor module decreases,
The present invention is applied to an optical device configured by mounting a plurality of motherboards in parallel, and has an effect of promoting miniaturization of the optical device.

Further, since there is no need for a printed wiring board different from the mother board and a case for accommodating the printed wiring board, there is an effect that the cost of the optical device is reduced accordingly.

Furthermore, since the guide groove provided in the package is inserted into the rectangular notch and the lead and the pad of the motherboard are connected, the mounting work of the optical semiconductor module is easy.

On the other hand, according to the third aspect of the invention, since the preamplifier is sealed in the package and shielded, the cost is lower than that in which the preamplifier is provided on the motherboard and the preamplifier is partially shielded. become.

[Brief description of drawings]

FIG. 1 is a perspective view of an embodiment of the present invention.

FIG. 2 is a side sectional view of an embodiment of the present invention.

FIG. 3 is a perspective view of another embodiment of the present invention.

FIG. 4 is a cross-sectional view of a conventional view (A) showing a mounting structure.

[Explanation of symbols]

1 Opto-semiconductor device 3,51
Lead 4 Stem 6 Lens 6A, 7 Lens holder 8 Optical fiber 9 Ferrule 20 Printed wiring board 21 Case 25,40
Motherboard 10,30 Opto-semiconductor module 31 Package 32 Side surface 33 End surface 34 Lid 35 Guide groove 41 Square notch 42,45
Pad 44 Sticking pad 55 Plate-shaped lead terminal

Claims (3)

[Claims] 1. A semiconductor module (3) comprising an optical semiconductor element and an optical fiber (8) optically coupled in a package (31).
0), the groove width formed parallel to the side surface (32) of the package (31) and parallel to the axis of the optical fiber (8) is the mother board (4
A pair of guide grooves (35) slightly larger than the plate thickness of (0) and leads (51) led out from the end surface (33) of the package (31).
And a rectangular notch formed on the motherboard (40) so that one side edge is open, the width of which is smaller than the width of the package (31) and the length of which is approximately equal to the length of the package (31). Four
1) and a pad (42) arranged on the motherboard (40) near the back side edge of the rectangular cut (41) so as to connect the leading ends of the respective leads (51), The mounting structure of an optical semiconductor module, wherein the guide groove (35) is inserted into and engaged with the rectangular notch (41), and the optical semiconductor module (30) is mounted on the motherboard (40). . 2. A semiconductor module (30) comprising an optical semiconductor element and an optical fiber (8) optically coupled in a package (31).
The groove width parallel to the axis of the optical fiber (8) formed on the side surface (32) of the package (31) is defined by the motherboard (4
A pair of guide grooves (35) slightly larger than the plate thickness of (0), the plate-shaped lead terminals (55) led out from the side surface (32) of the package (31), and one side edge side of which is opened. A square notch (4) provided on the mother board (40) whose width is desirably smaller than that of the package (31) and whose length is approximately equal to the length of the package (31).
1) and the pads (45) arranged on the motherboard (40) near the longitudinal side edges of the rectangular notches (41) so as to connect the tip ends of the respective plate-like lead terminals (55). And an optical semiconductor module (30) mounted on the mother board (40), the guide groove (35) being inserted into and engaged with the rectangular notch (41). Module mounting structure. 3. A substrate (38) sealed in the package (31) and having a preamplifier (39) formed thereon, and an optical semiconductor element which is a light receiving element mounted on the substrate (38).
The device according to claim 1, further comprising: (1) and a pad arranged on the substrate (38) to connect one end of the lead (51) or the plate-shaped lead terminal (55). Item 2. The mounting structure for an optical semiconductor module according to item 2.