JP2006032440A - Optical semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical semiconductor device which is improved to reduce a high chip unit price resulting from that a chip used as a light emitting element is larger than a wafer in size and a long-time process of forming an element, since an optical semiconductor element has complicated structure, namely, has superior optical characteristics. <P>SOLUTION: The optical semiconductor device 100 has an area where an electrode pad 117 is formed not on the top surface of the optical semiconductor element 112 by charging sealing resin 115 in a gap 114 formed at the circumference of the optical semiconductor element 112. Further, an electrode 116 has a shape having a gap inside, e.g. a ring shape. Therefore, the quantity of light outputted to the outside and emitted by the optical semiconductor element 112 increases and the light output efficiency of the optical semiconductor device 100 is improved. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an optical semiconductor device with improved light output efficiency and a method for manufacturing the same.

  An optical semiconductor element having an electrode pad on the top light emitting surface of the chip tends to set the size of one side of the electrode pad to 100 μm or more in consideration of a positional deviation error during bonding. However, when the size of one side of the electrode pad is 100 μm or more, the light output in the upper direction of the optical semiconductor element is hindered by the electrode, causing a decrease in light output efficiency. Therefore, there has been a demand for a structure that improves the electrode shape and improves the light output efficiency, and a method for manufacturing the structure.

  FIG. 8 shows the structure of the optical semiconductor device described in Patent Document 1.

n-type GaAs substrate an n-type AlAs current conduction region 2-1 as a light emitting region of the p / n structure on 1, n-type _Al 0.4 _{Ga 0.6} As layer 3, p-type _Al 0.15 _{Ga 0.85} As the layers 4, p-type _Al 0.4 _{Ga 0.6} as layer 5, ^{p +} -type GaAs layer 6 is epitaxially grown, a diagram illustrating a light emitting element section structures isolation in an island shape by photolithography and etching techniques. An Al _x O _y current blocking region 2-2 formed by oxidizing the n-type AlAs current-carrying region 2-1 and an intermediate insulating film 7 for the purpose of insulating the n-type substrate 1 are formed on the upper portion thereof. The light output region and the electrode region in which the p-side electrode 8 and the n-side electrode 9 are formed on the back surface of the substrate are configured as separate regions.

JP 2000-261029 A

  However, the prior art described in the above document has a large chip size used as a light emitting element with respect to the wafer size, resulting in a high chip unit cost, and the process of forming the element is long due to the complicated structure of the optical semiconductor element. There was room for improvement.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide an optical semiconductor device having excellent optical characteristics.

  According to the present invention, comprising an optical semiconductor element and a sealing resin provided around the optical semiconductor element, the electrode having an upper surface of the optical semiconductor element and an upper surface of the sealing resin, An optical semiconductor device is provided.

  According to the present invention, by providing the sealing resin around the optical semiconductor element, the electrode can be provided across the upper surface of the optical semiconductor element and the upper surface of the sealing resin. Therefore, a region for forming a part of the electrode can be provided in a portion other than the optical semiconductor element that is a light emitting region. Therefore, an optical semiconductor device with excellent optical characteristics can be provided.

  According to the present invention, there is provided a method of manufacturing an optical semiconductor device including an optical semiconductor element, the step of fixing a plurality of optical semiconductor elements on a tape, and extending the tape on which the plurality of optical semiconductor elements are fixed. A step of expanding a distance between the plurality of optical semiconductor elements, forming a gap between the plurality of optical semiconductor elements, a step of providing a sealing resin so as to embed the gap and the plurality of optical semiconductor elements, and a sealing resin Selectively exposing the upper surfaces of the plurality of optical semiconductor elements, and making the level of the upper surface of the sealing resin substantially the same as the level of the exposed upper surfaces of the plurality of optical semiconductor elements; And a step of forming an electrode straddling the upper surface of the optical semiconductor element and the upper surface of the sealing resin.

  According to the present invention, by expanding a tape on which a plurality of optical semiconductor elements are fixed, the distance between the optical semiconductor elements is increased, and a gap is formed between the optical semiconductor elements, and a sealing resin is provided in the gap. By including the steps, the optical semiconductor device can be provided by a simple process.

  According to the present invention, an optical semiconductor device having excellent optical characteristics is provided.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings, the same reference numerals are given to the same components, and the description will be omitted as appropriate.

  Hereinafter, the structure of the optical semiconductor device 100 will be described with reference to FIG.

  The optical semiconductor element 112 is, for example, a light emitting diode such as a gallium nitride-based compound semiconductor element, a semiconductor laser, or the like, and has a property of emitting light in a visible light to ultraviolet light region when a current flows. The main light emitting region is the upper surface of the optical semiconductor element 112, but has a property of emitting light also from the side surface.

  The sealing resin 115 is provided around the optical semiconductor element 112 and has optical transparency. Here, the optical output efficiency of the optical semiconductor device 100 is improved by the sealing resin 115 having optical transparency. Further, as the sealing resin 115, an insulating resin is used in order to suppress a short circuit between the p electrode (not shown) and the n electrode (not shown) of the optical semiconductor element 112.

  The electrode 116 is provided to allow a current to flow through the optical semiconductor element 112, and is formed in contact with the upper surface of the optical semiconductor element 112. Here, in order to ensure an effective light emitting region of the optical semiconductor element 112, the electrode 116 has, for example, a ring shape or the like having an air gap inside the outer shell. Hereinafter, in this embodiment, an effective light emitting region refers to a region that is not covered with an electrode or the like in the light emitting region of the optical semiconductor element.

  The electrode pad 117 is electrically connected to the electrode 116 and is provided in contact with the upper surface of the sealing resin 115. Here, when a voltage is applied to the electrode pad 117 using an external power supply, a current flows through the optical semiconductor element 112 via the electrode 116.

  A manufacturing process of the optical semiconductor device 100 according to the present embodiment will be described with reference to FIGS.

  First, as shown in FIGS. 2A and 2B, the wafer 111 is diced into a plurality of optical semiconductor elements 112 having a size of about 0.5 mm square, for example. Here, FIG. 2B is a cross-sectional view taken along the line AA ′ of FIG. In FIG. 2A, the periphery of the lead line of the optical semiconductor element 112 is outlined, but it is assumed that the optical semiconductor element 112 is continuously formed.

  Next, as shown in FIGS. 3A and 3B, after the plurality of optical semiconductor elements 112 are attached and fixed to the tape 113, the tape 113 is heated to attach the plurality of optical semiconductor elements 112 to each other. By stretching the attached and fixed tape 113, the distance between the plurality of optical semiconductor elements 112 is increased, and a gap 114 (FIG. 4) is formed between the optical semiconductor elements 112. Here, there may be a gap between the plurality of optical semiconductor elements 112 before being stretched, or may not have a gap due to close contact between the plurality of optical semiconductor elements 112. Here, FIG. 3B is a cross-sectional view taken along the line AA ′ of FIG. 3A. In FIG. 3A, the periphery of the lead line of the optical semiconductor element 112 is outlined. Assume that 112 is formed continuously. The material of the tape may be any material that can adhere to the optical semiconductor element 112 and has elasticity when heated. As the material, for example, a vinyl chloride film is used.

  By stretching the tape 113 to which the plurality of optical semiconductor elements 112 are attached, a gap 114 is formed between the optical semiconductor elements 112 as shown in FIGS. 4 (a) and 4 (b). Here, FIG. 4B is an AA ′ sectional view of FIG. Next, a sealing resin 115 is provided so as to embed the gap 114 and the upper surfaces and side surfaces of the plurality of optical semiconductor elements 112 (FIGS. 5A and 5B). Further, the sealing resin 115 is light transmissive. Since the sealing resin 115 has light transmittance, the amount of light output from the optical semiconductor device 100 to the outside increases. Here, FIG. 5B is an AA ′ sectional view of FIG.

  Next, the top surface of the optical semiconductor element 112 is exposed by cueing each optical semiconductor element 112 using a method such as etching on the upper surface of the sealing resin 115 (FIG. 6A and FIG. 6). b)). At this time, the level of the upper surface of the optical semiconductor element 112 and the level of the upper surface of the sealing resin 115 are substantially the same. Here, “substantially the same” means the level of the upper surface of the optical semiconductor element 112 when cueing the upper surface of the sealing resin 115 and the upper surface of the optical semiconductor element 112 simultaneously using a method such as etching. The variation between the level of the upper surface of the sealing resin 115 is allowed. Here, FIG. 6B is an AA ′ sectional view of FIG. Subsequently, an electrode 116 patterned into an annular shape having a gap inside, for example, a ring shape or the like is formed on the upper surface of each optical semiconductor element 112, and a sealing provided between the optical semiconductor elements 112. An electrode pad 117 is formed on the resin 115 so as to extend from each electrode 116 so as to straddle the upper surface of the optical semiconductor element 112 and the upper surface of the sealing resin 115 (FIGS. 7A and 7B). Here, FIG. 7B is an AA ′ sectional view of FIG.

  The optical semiconductor device 100 can be manufactured by the above process.

  Hereinafter, the effects of the optical semiconductor device 100 according to the present embodiment and the manufacturing process thereof will be described.

  In the optical semiconductor device 100, the sealing resin 115 is embedded in the gap 114 formed around the optical semiconductor element 112, whereby an electrode that is electrically connected to the electrode 116 in a region other than the upper surface of the optical semiconductor element 112 that is a main light emitting region. A pad 117 is formed. Therefore, the area of the electrode 116 provided in contact with the upper surface of the optical semiconductor element 112, which is the main light emitting region, can be made smaller than the area of the electrode provided in contact with the upper surface of the optical semiconductor element in the prior art. As a result, more effective light emitting regions of the optical semiconductor element 112 can be secured. Therefore, the amount of light output from the optical semiconductor element 112 to the outside increases.

  Here, since the surface area of the electrode 116 on the optical semiconductor element 112 is narrower than that of the conventional electrode structure, the amount of current flowing through the optical semiconductor element 112 is slightly lower than that of the conventional technique. Therefore, the amount of light emitted from the optical semiconductor element 112 is slightly smaller than the amount of light emitted from the optical semiconductor element in the prior art by the amount of current reduction, but the area of the electrode 116 provided in contact with the upper surface of the optical semiconductor element 112 is as follows. It is sufficiently narrow compared with the area of the electrode in the prior art. In addition, the contribution ratio of the optical semiconductor device 100 to the amount of light output to the outside is considered to be greater in the degree of expansion of the effective light emitting region due to the electrode area becoming narrower than the degree of reduction in the amount of current. Therefore, the amount of light output from the optical semiconductor device 100 to the outside is larger than the amount of light output from the optical semiconductor device in the prior art to the outside.

  Further, the gap 114 around the optical semiconductor element 112 is formed by expanding the tape 113 to which the optical semiconductor element 112 is attached and fixed, and the sealing resin 115 is embedded in the gap 114 to thereby form an electrode pad. A region where 117 is provided is formed. That is, the region where the electrode pad 117 is provided is formed by a simple process of expanding the tape 113 and embedding the sealing resin 115. Therefore, more effective light emitting regions of the optical semiconductor element 112 can be efficiently secured. Therefore, among the light emitted from the optical semiconductor element 112, the amount of light output to the outside can be increased efficiently.

  The shape of the electrode 116 is, for example, an annular shape having a void portion inside the outer portion, such as a ring shape. Since the shape of the electrode 116 is an annular shape, the area of the electrode 116 provided in contact with the upper surface of the optical semiconductor element 112 which is a main light emitting region can be further reduced, so that the optical semiconductor element 112 can effectively emit light. More area can be secured. Therefore, the amount of light output to the outside among the light emitted from the optical semiconductor element 112 is further increased.

  In the optical semiconductor device 100, a light-transmitting sealing resin 115 is used. By using the light-transmitting sealing resin 115, the amount of light transmitted through the sealing resin 115 out of the light emitted from the side surface of the optical semiconductor element 112 is increased. Accordingly, among the light emitted from the optical semiconductor element 112, the amount of light emitted from the optical semiconductor device 100 through the sealing resin 115 is further increased.

  Further, in the manufacturing process of the optical semiconductor device 100, the tape 113 to which the optical semiconductor element 112 is attached and fixed is expanded to form a gap 114 around the optical semiconductor element 112, and the sealing resin 115 is embedded in the gap 114. Thus, a region for forming the electrode pad 117 is formed. Therefore, the optical semiconductor device 100 with improved light output efficiency can be manufactured by adding a simple process of expanding the tape 113 and embedding the sealing resin 115. In addition, the tape 113 to which the optical semiconductor element 112 is attached and fixed is expanded to form a gap 114 in which the sealing resin 115 in which the electrode pad 117 is formed is embedded. It's not big. That is, in the optical semiconductor device 100, the effective light emitting region is not widened by increasing the size of the optical semiconductor element 112, but by securing a region for forming the electrode pad 117 around the optical semiconductor element 112. The effective light emitting area is widened. Therefore, it is possible to widen the effective light emitting region of the optical semiconductor element 112 while suppressing the generation of the cost required when increasing the size of the optical semiconductor element 112. Therefore, the optical semiconductor device 100 with improved light output efficiency can be manufactured with a simple process and low cost.

  As mentioned above, although embodiment of this invention was described with reference to drawings, these are the illustrations of this invention, Various structures other than the above are also employable.

  For example, in the above-described embodiment, an embodiment using an annular electrode such as a ring shape has been described as the electrode 116. However, even in other shapes, the outer portion is shaped like a rectangle with a hollow interior. As long as it has a shape having a gap inside and a contact area with the upper surface of the optical semiconductor element 112 is narrow, an effective light emitting region of the optical semiconductor element 112 can be increased. Moreover, even if it is an electrode other than cyclic | annular form, what is necessary is just to comprise a part of electrode straddling optical semiconductor element and sealing resin.

  Moreover, in the said embodiment, although the form which used resin which has a light transmittance as sealing resin 115 was demonstrated, resin which does not have a light transmittance may be sufficient.

It is sectional drawing which showed typically the structure of the optical semiconductor device which concerns on embodiment. It is sectional drawing which showed typically the manufacturing process of the optical semiconductor device which concerns on embodiment. It is sectional drawing which showed typically the manufacturing process of the optical semiconductor device which concerns on embodiment. It is sectional drawing which showed typically the manufacturing process of the optical semiconductor device which concerns on embodiment. It is sectional drawing which showed typically the manufacturing process of the optical semiconductor device which concerns on embodiment. It is sectional drawing which showed typically the manufacturing process of the optical semiconductor device which concerns on embodiment. It is sectional drawing which showed typically the manufacturing process of the optical semiconductor device which concerns on embodiment. It is the figure which showed typically the optical semiconductor device which concerns on a prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Optical semiconductor device 111 Wafer 112 Optical semiconductor element 113 Tape 114 Crevice 115 Sealing resin 116 Electrode 117 Electrode pad

Claims (4)

An optical semiconductor element;
A sealing resin provided around the optical semiconductor element;
With
An optical semiconductor device comprising an electrode straddling the upper surface of the optical semiconductor element and the upper surface of the sealing resin. The optical semiconductor device according to claim 1,
A shape of a portion of the electrode in contact with the upper surface of the optical semiconductor element is annular. The optical semiconductor device according to claim 1 or 2,
An optical semiconductor device, wherein the sealing resin is a light-transmitting sealing resin. A method of manufacturing an optical semiconductor device comprising an optical semiconductor element,
Fixing a plurality of optical semiconductor elements on the tape;
Extending the distance between the plurality of optical semiconductor elements by expanding the tape to which the plurality of optical semiconductor elements are fixed, and forming a gap between the plurality of optical semiconductor elements;
Providing a sealing resin so as to embed the gap and the plurality of optical semiconductor elements;
The sealing resin is selectively removed, the upper surfaces of the plurality of optical semiconductor elements are exposed, and the level of the upper surface of the sealing resin and the level of the upper surfaces of the exposed plurality of optical semiconductor elements are approximately The same process;
Forming an electrode straddling the upper surface of the plurality of optical semiconductor elements and the upper surface of the sealing resin;
A method of manufacturing an optical semiconductor device comprising:

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