JPS6144456Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a semiconductor device, and particularly to an improved structure of a light emitting display surface.

An optical semiconductor device that produces a surface-emitting display by sealing an assembly in which a light-emitting element is attached to a lead frame or a printed wiring board with pin terminals and wired with a light-transmitting synthetic resin that has been given light-scattering properties. be. The structure of this example is shown in perspective views in both FIG. 1 and FIG. 3. First, the one shown in Figure 1 is lead 1,
The light emitting element 2 is fixed to the light emitting element attachment part 1a formed by widening the end of one lead 1 of the lead 1' with an electrode (not shown) on one main surface thereof, and the other electrode 3 is bonded. The periphery of the assembly 5 connected to the other lead 1' by a wire 4 is molded and sealed with epoxy resin 6 or the like, and its upper main surface is used as a light emitting main surface. Note that the light emitting element attachment member to which the light emitting element is attached may be attached to the end of the lead as described above.
It may also be a printed circuit board or the like. Such a structure is assembled in a cavity 7a provided in a mold 7, as shown in a perspective view in FIG.
5 is molded with epoxy resin. Next, as shown in FIG. 3, the assembly 5 is made of, for example, noryl resin and has a side frame 8 made of a light reflective material that covers the entire side surface of the optical semiconductor device (particularly, this is shown in a perspective view in FIG. 4). It is molded and sealed inside.

The optical semiconductor device having the structure described above has the following drawbacks. That is, in the case of the structure shown in FIG. 1, the light emitted from the side surface of the light emitting element directly becomes the light emitted to the side of the molded resin body 6, and does not contribute to the desired light emission from the upper principal surface, so that the luminous intensity is low. There are drawbacks such as uneven brightness distribution on the light emitting surface. Next, the structure shown in FIG. 3 is one in which a side frame 8 is provided at the same height as the top surface (light emitting display surface) of the light scattering resin so as to block and reflect light emitted from the side surface in FIG. The light emitted from the side is blocked, and although a small portion of it slightly contributes to the light emission of the light emitting display surface, the end face of the side frame is exposed at the edge of the light emitting display surface, creating a "shade". There is a drawback. Next, when such optical semiconductor devices are connected to display a character shape, or when they are arranged two-dimensionally to form a large area light emitting surface, the character shape may be distorted due to the above-mentioned "shading" when used as a single device. It has the disadvantage of creating base marks in divided or widely displayed areas, which can be very unsightly.

This invention provides a structure of an optical semiconductor device to improve the above-mentioned conventional drawbacks.

The optical semiconductor device according to this invention includes a semiconductor light emitting element, a light emitting element attachment member to which the semiconductor light emitting element is attached, and a light emitting element on the side of the main surface of the semiconductor light emitting element. a light-scattering resin envelope that integrally encloses the semiconductor light-emitting element, the mounting member, and the reflector; the upper surface of the envelope serves as a light-emitting display surface; In such an optical semiconductor device, a flat light-emitting display surface made of a thick light-scattering resin on a reflector is located upwardly away from the top surface of the reflector, and the outermost edge of the light-emitting display surface is above the reflective surface. It is characterized by being located inside the extension of the light emitting display surface, which eliminates shadowing caused by the upper surface of the reflector and provides uniform brightness to the edges.

Next, one embodiment of this invention will be explained in detail with reference to the drawings. As shown in a perspective view in FIG. 5, a sectional view in FIG. 6, and a perspective view of a reflector in FIG. An assembly 5 (FIG. 6) in which a light emitting element 2 is fixed to the attachment part 1a with an electrode on one main surface of the element and the other electrode 3 is connected to the other lead 1' with a bonding wire 4 is assembled to the reflector 11. match. This reflector is made of Noryl resin, ABS resin, etc. with good reflectance, and is formed into a box shape with an open top, as shown in FIG. A reflective surface 11b is formed to surround the light emitting element of the assembly inserted from the light emitting element so as to reflect light emitted from the side surface of the light emitting element in the light emitting direction of the main surface. In addition, on the outer surface, there is a step as an example for forming the edge of the coating in mold sealing with light scattering resin, which will be described later.
1c is provided. Furthermore, a light-scattering resin body 16 that integrally envelops the assembly and the reflector is formed by molding, for example, an epoxy resin mixed with a light-scattering agent on the reflector to form an envelope. In this case, the thickness h (FIG. 6) of the light-scattering resin body on the edge of the top surface of the reflector is increased to a predetermined value, and the light-emitting display surface is positioned away from the edge of the top surface of the reflector by the distance h.
Here, the thickness depends on the size, structure, and thickness of the optical semiconductor device.
Although it may be practically determined in advance based on the light scattering properties of the light scattering resin, as shown in FIG. Decide so that there is. This type of structure has a reflector inside, which makes the light-emitting display surface sufficiently bright and uniform in brightness, and the light-scattering resin is formed thickly so that the light-emitting display surface is separated from the top surface of the reflector. The light emitting display surface will not be obscured by the reflector. Furthermore, since the light-scattering resin is coated on the outer periphery of the reflector, the reflective surface and the light-scattering resin will not separate from each other.

Next, FIGS. 8 and 9 show an example of a method for manufacturing an optical semiconductor device. That is, FIG. 8 is a perspective view of a sealing cap 17 that becomes a part of the envelope, and is made of a light-scattering or transparent synthetic resin.
As shown in the cross-sectional view in the figure, the opening is facing upward, and a light scattering resin (viscous type) 16' is put inside and set.
After the reflector 11 and the assembly 5 are inserted, they are heated to solidify the light-scattering resin and sealing is achieved. With such a structure, the sealing device is simple and a high-precision molding device is not required. Furthermore, there is no need to worry about dirt on the inner surface of the mold (adhesion of cured resin), which is characteristic of resin molding devices, and the product has the advantage of having a significantly better appearance.

Further, FIGS. 10 and 11 show perspective views of the external appearance of another embodiment of the reflector. All of these differ in the shape of the portion where the light-scattering resin or the sealing cap contacts the peripheral surface of the reflector. first,
The tenth reflector 21 has a slope portion 21a,
Using a mold in which the adhesive end with the light-scattering resin becomes the extended part 21b of the slope, that is, a mold 7 with a cavity in which the extended part of the slope is brought into close contact with each other, as shown in the cross-sectional view in FIG. All you have to do is apply. In addition, when a sealing cap is used, the cap is sealed by making close contact with the extended portion of the slope. A reflector 31 shown in FIG. 11 has a sloped protrusion 31a into which a sealing cap is fitted to achieve sealing. In this way, the slope or the protrusion can be provided at any part of the side surface, and the edge of the sealing adhesive between the light-scattering resin and the reflector can be set as desired.

According to this invention, a flat light-emitting display surface is formed of a light-scattering resin at a predetermined distance from the top surface of the reflector, and the light-emitting display surface is located upwardly from the top surface of the reflector. The outermost edge of the display surface is on the inner surface of the upward extension of the reflective surface;
In other words, since the upper edge of the reflector is located outside the range connecting the outermost edge of the light-emitting display surface and the upper edge of the reflective surface of the reflector, the "shading" caused by the top surface of the reflector is displayed in the light-emitting display. A uniform and bright light-emitting display surface can be formed without causing any generation of light on the surface. Therefore, even when used as a standalone optical semiconductor device, there is an advantage that the light-emitting display surface is uniform and bright all the way to the edges, and there is no "shading".
In addition, when connecting to form a character shape, it expresses a completely connected and beautiful character shape, and when connecting two-dimensionally to form a wide area light emitting surface, it forms a wide area light emitting surface without a grid pattern. There is a distinct advantage that it can be done.
Furthermore, this invention is easy to implement, the product is inexpensive, and has a strong structure that prevents peeling between the reflector and the light-scattering resin.

[Brief explanation of drawings]

1 and 3 are perspective views each showing a conventional optical semiconductor device, FIG. 2 is a perspective view for explaining mold sealing of the optical semiconductor device, and FIG. 4 is a perspective view of a conventional optical semiconductor device. A perspective view showing the side frame of the optical semiconductor device shown in FIG. 5 and subsequent figures relate to this invention.
FIG. 5 is a perspective view of an optical semiconductor device according to an embodiment of this invention, FIG. 6 is a sectional view of FIG. 5, FIG. 7 is a perspective view of a reflector, and FIG. 8 is a perspective view of a sealing cap. , FIG. 9 is a sectional view for explaining sealing using a sealing cap, FIGS. 10 and 11 are perspective views of a reflector, and FIG. 12 is a mold sealing of an optical semiconductor device. It is a sectional view for explaining a stop. 1,1'...Lead, 2...Light emitting element, 5 ...
Assembly, 11 , 21 , 31 ...Reflector, 11b...
... Reflective surface, 16 ... Light-scattering resin, 17 ... Sealing cap, 21a ... Slope portion on side surface of reflector, 3
1a... Projection on the side surface of the reflector.

Claims (1)

[Scope of utility model registration request] A semiconductor light-emitting element, a light-emitting element mounting member to which the semiconductor light-emitting element is attached, and a reflection device comprising a reflective surface that reflects light emitted from the side of the semiconductor light-emitting element toward the light emission direction of the main surface. an optical semiconductor device comprising a light-scattering resin envelope integrally enclosing the semiconductor light-emitting element, the mounting member, and a reflector, the upper surface of the envelope being a light-emitting display surface; A flat light-emitting display surface made of a thick layer of light-scattering resin is located upwardly away from the top surface of the reflector, and the outermost edge of the light-emitting display surface is located inside the upward extension of the reflective surface. Optical semiconductor device.