JPH10341062A - Light-emitting device module and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To thin a device with a simple structure by mounting a light-emitting device and a photodetector for monitoring on a silicon substrate in a horizontal direction and in parallel. SOLUTION: A photo detector 12 for a backside incidence-type monitor is mounted on an Si(silicon) substrate 13 so that it becomes flush with a light- emitting device 11. A V-shaped groove for guiding a beam is formed at a backside 18 of the light emitting device 11, so that a backside emission beam 14 from the light-emitting device 11 is not reflected by the Si substrate 13 with transmission property, and furthermore an AR coating 15 is applied onto one side of the V-shaped groove for guiding the beam to prevent reflection. The lower part of the photo detector 12 for monitoring is subjected to skew cutting and metal coating 16 to entirely reflect incident beams from the V-shaped groove. Then, the backside emission beam of the light-emitting device 11 once enters the Si substrate 13 and furthermore is reflected on the backside of the Si substrate 13 before being received by the photo detector 12 for monitoring, this thinning the thickness of a module body.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a light emitting module and a method for manufacturing the same.

[0002]

2. Description of the Related Art A conventional light emitting element module is a CAN.
Based on a (can) type package, a monitor light receiving element is mounted vertically to the light emitting element, and the light emitted from the back surface of the light emitting element is directly received.

FIG. 4 shows a schematic structure of a conventional light emitting element module. FIG. 4 is a diagram showing a cross section of a light emitting element module proposed in Japanese Patent Application Laid-Open No. 1-260882. Referring to FIG. 4, this conventional light emitting element module has a flat or concave portion in which a reflective coating is formed on a part of the surface of the lens facing the light emitting element. FIG.
1 shows a configuration of another conventional light emitting element module.

[0004]

When the light emitting element module is driven, a part of the light emitted from the back surface of the light emitting element is subjected to negative feedback as a monitor signal, and APC driving (Automatic Power Control) for keeping the light output level constant. Is used.

For this purpose, a light receiving element for monitoring is mounted,
Light emitted from the back surface of the light emitting element is received.

FIG. 5 is a sectional view showing an example of the configuration of a conventional coaxial light emitting element module. Referring to FIG. 5, this conventional light-emitting element module is based on a CAN type package 501, and a monitor light-receiving element 503 has a light-emitting direction of a light-emitting element 502 and a light-receiving surface of the light-receiving element.
It is necessary to mount on the L-shaped stem 504 perpendicular to the light emitting element 502.

As shown in FIG. 5, the conventional light-emitting element module has a problem that the number of parts is large, the module structure is complicated, and the number of steps for assembling the module is large.

The size of the monitor light receiving element 503 is about 1 mm × 1 mm × 0.3 mm. When the light receiving element 503 is vertically mounted on a stem, the size of the light emitting element module in the thickness direction depends on its size. There has been a limitation on miniaturization of the light emitting element module.

Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to provide a thinner module having a simpler structure than a conventional light emitting element module.

[0010]

According to the present invention, there is provided a light emitting element module having a light emitting element and a monitor light receiving element, wherein the light emitting element and the monitor light receiving element are provided on a silicon substrate. It is mounted parallel to the horizontal direction.

The present invention also provides a light-emitting element module having a light-emitting element and a monitor light-receiving element built therein, wherein the light-emitting element and the monitor light-receiving element are horizontally mounted on a silicon substrate. Light emitted from the back surface is once incident on the silicon substrate, reflected on the back surface of the silicon substrate, and then received by the monitor light receiving element.

Further, the present invention has a light guide groove on the silicon substrate between the light emitting element and the light receiving element, and a reflection groove on a back surface of the silicon substrate below the light receiving element. It has an oblique cut portion.

Further, according to the manufacturing method of the present invention, the light emitting element and the monitoring light receiving element are horizontally mounted on the silicon substrate, the light emitted from the back surface of the light emitting element is once incident on the silicon substrate, After being reflected by the back surface, the light is received by the monitor light-receiving element. In the method for manufacturing a light-emitting element module, the light-receiving element is provided on the silicon substrate between the light-emitting element and the light-receiving element. After forming a groove, applying an AR coating and a metal coating, and horizontally arranging the light emitting element, the light receiving element for monitoring, and the optical fiber on the silicon substrate, then sealing them with a potting resin, and then molding them into a mold resin. And sealing.

[0014]

Embodiments of the present invention will now be described with reference to the drawings.

FIG. 1 is a sectional view showing the configuration of a module according to an embodiment of the present invention. The back-illuminated monitoring light-receiving element 12 is mounted on a Si (silicon) substrate 13 horizontally with the light-emitting element 11. Backside emitted light 14 from light emitting element 11
A light-guiding V-shaped groove is dug in the back surface side 18 of the light emitting element 11 so that the light is not reflected by the transmissive Si substrate 13. AR coating (Anti Reflection Coating) 1 on one side
5 is given.

On the other hand, the monitoring light receiving element 1 of the Si substrate 13
The oblique cut and the metal coating 16 are applied to the lower part of 2 to totally reflect the light incident from the V-shaped groove.

Next, a manufacturing flow of the light emitting element module according to the embodiment of the present invention will be described with reference to FIG.

First, a V-shaped groove is dug in a Si substrate, and an AR coating and a metal coating are applied.

Next, the light emitting element 11 and the monitoring light receiving element 12
After arranging the optical fibers 17 horizontally on the Si substrate 13, the optical fibers 17 are then sealed with a potting resin 19, and they are sealed with a mold resin 20 having a light shielding property.

The light emitting element module according to the embodiment of the present invention has a thickness of about 2 mm to 3 mm by eliminating the L-shaped stem and mounting the monitoring light receiving element horizontally with the light emitting element. That is, the thickness of the module body can be reduced.

Table 1 shows the output of the monitoring light receiving element calculated from the optical length from the back surface of the light emitting element 11 to the monitoring light receiving element 12.

[0022]

[Table 1]

The conventional light emitting element module has an optical length of about 500 μm.
The refractive index of the Si substrate: n can be set to 400 μm or less, where n = 3.5. Thus, the output of the monitoring light receiving element of the conventional light emitting element module is about 100 μA to 700 μA, whereas the output of the monitoring light receiving element of the light emitting element module of this embodiment is 150 μA to 1100 μA.
About A or more is possible, and it can be understood that the embodiment of the present invention is more advantageous.

FIG. 2A is a diagram showing the configuration of the second embodiment of the present invention. After a light emitting element (LD; laser diode) 11, a monitoring light receiving element (PD; photodiode) 12, and an optical fiber 17 are horizontally arranged on a Si substrate 13, they are sealed with a potting resin 19, and these are primary. Alternatively, a configuration may be adopted in which the area corresponding to the upper surface of the monitoring light receiving element (PD) 12 of the light shielding secondary mold resin is cut obliquely.

FIG. 2B is a sectional view showing the structure of the third embodiment of the present invention. After the light emitting element (LD) 11, the monitor light receiving element (PD) 12, and the optical fiber 17 are horizontally arranged on the Si substrate 13, they are sealed with a potting resin 19, and these are molded into primary and secondary molding resins. The reflection type lens may be configured such that a region corresponding to the upper surface of the monitoring light receiving element of the secondary mold resin for light shielding is curved.

[0026]

As described above, according to the present invention, the following effects can be obtained. The diameter of the conventional coaxial light-emitting element module body is usually about 6 mm to 7 mm. However, the light-emitting element module of the present invention requires the removal of the L-shaped stem and the mounting of the monitoring light-receiving element horizontally with the light-emitting element. Thus, the thickness can be preferably about 2 mm to 3 mm. That is, the thickness of the module body can be reduced.

Also, it can be understood that the present invention has a higher output of the monitoring light receiving element than the conventional light emitting element module, and that the present invention is more advantageous.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a structure of a light emitting element module according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view illustrating a structure of a light emitting element module according to another embodiment of the present invention.

FIG. 3 is a flowchart for producing a light-emitting element module according to an embodiment of the present invention.

FIG. 4 is a diagram showing a configuration of a conventional light emitting element module.

FIG. 5 is a diagram showing a configuration of a conventional light emitting element module.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Light emitting element 12 Monitor light receiving element 13 Si substrate 14 Back side emitted light 15 AR coating 16 Metal coating 17 Optical fiber 19 Potting resin 20 Mold resin

Claims (6)

[Claims] 1. A light-emitting element module including a light-emitting element and a monitor light-receiving element, wherein the light-emitting element and the monitor light-receiving element are mounted on a substrate in parallel in a horizontal direction. module. 2. A light-emitting element module incorporating a light-emitting element and a monitor light-receiving element, wherein the light-emitting element, the monitor light-receiving element, and the optical fiber are horizontally arranged on a substrate, and then sealed with a potting resin. These are sealed with a primary and secondary molding resin, and a region corresponding to the upper surface of the monitor light receiving element on the inner wall of the secondary molding resin for shading is obliquely cut. Light emitting element module. 3. A light-emitting element module incorporating a light-emitting element and a monitor light-receiving element, wherein the light-emitting element, the monitor light-receiving element, and the optical fiber are horizontally arranged on the substrate, and then sealed with a potting resin. And sealed with these primary and secondary molding resins,
A light-emitting element module comprising: a reflective lens having a curved surface area corresponding to the upper surface of the monitor light-receiving element on the inner wall of the secondary mold resin for shading. 4. A light-emitting element module having a light-emitting element and a monitor light-receiving element built therein, wherein the light-emitting element and the monitor light-receiving element are horizontally mounted on a silicon substrate, and light emitted from the back surface of the light-emitting element is provided. Once incident on the silicon substrate and further reflected on the back surface of the silicon substrate,
A light-emitting element module configured to be received by the monitor light-receiving element. 5. A light guide groove is formed on the silicon substrate between the light emitting element and the light receiving element, and an oblique cut portion for reflection is formed on a back surface of the silicon substrate below the light receiving element. The light emitting device module according to claim 1, comprising: 6. A light-emitting element and a monitor light-receiving element are mounted horizontally on a silicon substrate, and light emitted from the back surface of the light-emitting element is once incident on the silicon substrate and reflected on the back surface of the silicon substrate. A method for manufacturing a light emitting element module configured to receive light by the monitor light receiving element, wherein a light guide groove is provided on the silicon substrate between the light emitting element and the light receiving element; After applying a metal coating, the light emitting element, the monitor light receiving element and the optical fiber are horizontally arranged on the silicon substrate, and thereafter sealed with a potting resin, and then sealed with a mold resin. A method for manufacturing a light-emitting element module, comprising: