JPH0228974A - Optical semiconductor device - Google Patents

Abstract

PURPOSE:To enable noise caused by reflected light by the inner face to be reduced easily to a substantial extent by providing a recessed section on the surface of sealing resin while inclining the surface of the recessed section by a predetermined angle. CONSTITUTION:A semiconductor resin package consists of a semiconductor mounting section 7, a lead frame 2, a sealing resin 1, a semiconductor element 3 and a resin surface recessed section 4. The recessed section 4 is inclined by 1 to 10 deg. relative to the surface of the semiconductor element by an injector pin. The semiconductor element 3 is a photodiode divided into four equal sections, namely quartered into four elements having a photodetecting size of 80mum square. Incident laser light 5 will be refracted since the surface of the recessed section 4 is inclined relative to the surface of the semiconductor element 3 and enters into all the elements of the photodiode. A part of the incident light is reflected by the photodetecting section 3' and reflected light 6 will be incident again on the inner face of the resin but does not return to the photodetecting section.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an optical semiconductor device in which a photoelectric conversion element is molded in a resin molding, in which a recessed portion having a certain angle is provided on the surface of a resin portion on the optical path side. It is related to.

2. Prior Art A plan view and a cross-sectional view of a conventional optical semiconductor device are shown in Figure 2 (a).
, shown in (b). The surface of the sealing resin 1 is flat, and the lead part 2 and the element mounting part 7 are formed into a flat plate, and the semiconductor element 3 is mounted thereon and used.

Problems to be Solved by the Invention In a conventional optical semiconductor, the element mounting part 7 and the lead part 2
are formed on the same flat plate, and the surface of the sealing resin 1 is parallel to this. For this reason, when light from a light source such as a semiconductor laser is incident, the light reflected component on the inner surface of the resin re-enters the element section, causing a problem of a lot of noise.In particular, as an element section, the photoelectric conversion section In the case of a micro-sized type with multiple divisions, there is a drawback that unnecessary light enters adjacent elements.

The present invention attempts to solve such problems, and aims to easily reduce noise in a semiconductor element having a simple structure by changing the structure of the sealing resin.

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention forms a recessed portion having a certain angle on the surface of the sealing resin of a semiconductor element.

According to the present invention, noise caused by internal reflection of the sealing resin can be significantly reduced by providing a depressed portion on the surface of the sealing resin of the semiconductor element and providing an angle of 1 to 10 degrees with respect to the semiconductor element mounting portion. Can be reduced.

Embodiment FIGS. 1(a) and 1(b) show an embodiment showing a plan view and a sectional view of a semiconductor resin package of the present invention. Semiconductor device section 7. Lead frame 2. Sealing resin 1° Semiconductor element 3. It is composed of a resin surface depression part 4. The resin surface depression portion 4 is formed at an angle of 4° with respect to the semiconductor element surface by, for example, an injector turbine. According to experience, a suitable angle for this angle is 1° to 10". A 4-part photodiode is used as the semiconductor element 3, and the light-receiving area has 4 elements with an opening of 80 μm arranged in a square shape. The separation width is 15 μm.Epoxy translucent resin is used as the sealing resin.

When the laser beam 5 is incident, since the recessed surface 4 has an angle with respect to the surface of the semiconductor element 3, it is refracted and incident on each element of the photodiode. A part of the incident light is reflected by the light receiving section 3', and the reflected light 6 enters the inner surface of the resin again, but does not return to the light receiving section.

In this way, according to this embodiment, the noise caused by the light reflected from the inner surface of the resin can be easily reduced by making the surface of the recessed part on the resin surface, which serves as the optical path, at an angle of 1° to 10'' with respect to the semiconductor element surface. In this example, by providing an angle of 4 degrees, it was possible to achieve a noise reduction of 1/3 or less.

Effects of the Invention As described above, according to the present invention, by providing a recessed portion and a predetermined angle on the resin sealing surface, it is possible to easily and significantly reduce noise caused by internally reflected light.

[Brief explanation of the drawing]

FIG. 1 is a plan view and a sectional view of an optical semiconductor device according to an embodiment of the present invention, and FIG. 2 is a plan view and a sectional view of a conventional example. 1...Resin for sealing semiconductor elements, 2...
Lead part, 3...Semiconductor element, 3'...
・Light receiving part, 4... Depression part due to injector turbine, 5... Laser light, 6... Reflected light from inner surface of resin, 7... Semiconductor device part . Name of agent: Patent attorney Shigetaka Awano and one other person Figure 1 (α) Fuun

Claims (1)

[Claims] Place the optical semiconductor device on the device placement part of the lead frame,
It is characterized in that it is sealed with a translucent resin, a recessed part is provided on the surface of the resin sealing part on the optical path side, and the surface of the recessed part is set at an angle of 1 to 10 degrees with respect to the element mounting part. Optical semiconductor device.