JP2010245182A - Method of manufacturing semiconductor light emitting device, and method of forming light reflection film of light emitting element bar - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a semiconductor light emitting device in which occurrence of a material loss is avoided as far as possible and a light reflection film is formed with an inexpensive technique. <P>SOLUTION: The method of manufacturing the semiconductor light emitting device includes the processes of: (A) forming the laminate structure 20 of a compound semiconductor layer; sticking a rectangular substrate 40 having a first side, a second side, a third side, and a fourth side on a support film 50 such that the support film 50 protrudes from at least the second side 42 of the substrate; marking off the support film 50 and substrate 40 in parallel with an X direction; cleaving the substrate 40; tearing the support film 50 to obtain a light emitting element bar 60; laminating a plurality of light emitting element bars 60, heating the support film 50 so that the support film 50 thermally shrinks along a Y direction, and providing a gap between XZ ends 61, 62 of the light emitting element bar 60 and the edge of the support film 50; and forming light reflection films 63, 64 on the two XZ ends 61, 62 of each light emitting element bar 60. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a semiconductor light emitting device and a method for forming a light reflecting film in a light emitting element bar.

  As a high-power semiconductor laser device, a light-emitting element having a length of about 10 mm, comprising a light-emitting element array in which a plurality of (for example, several to about 50) semiconductor laser elements are arranged in a row so that the laser beam emission directions are aligned. Bars are often used.

  In order to manufacture the light emitting element bar, first, an element manufacturing process is performed by forming a light emitting portion composed of a laminated structure of compound semiconductor layers on an element manufacturing substrate (so-called wafer), and further forming electrodes and the like. A large number of light-emitting elements are manufactured on a substrate for use. Thereafter, the element manufacturing substrate is divided into several rectangular substrates, and each of the rectangular substrates is attached to a dicing sheet. Then, a scribing line having a depth of several μm is put on the surface of the substrate by a scribing device. Next, the substrate divided into rectangular shapes is cleaved by a break machine. Alternatively, when a roller is rolled with a rubber roller while applying pressure from the dicing sheet side, the substrate divided into rectangular shapes is cleaved. In this manner, a plurality of light emitting element bars can be obtained from one rectangular substrate.

Thereafter, a light reflecting film is formed on the cleavage surface of the light emitting element bar. Specifically, the dicing sheet to which the light emitting element bar is attached is stretched to open a gap between the light emitting element bar and the light emitting element bar. Next, the light emitting element bars are peeled off from the dicing sheet one by one using a tool such as tweezers. Then, the peeled light emitting element bars are placed one by one in an end surface coating jig. Thereafter, a jig containing about 100 light emitting element bars is carried into a vacuum deposition apparatus, and a light reflecting film made of Al ₂ O ₃ or amorphous Si is deposited. Finally, the light emitting element bar is attached to the base (heat sink) using, for example, solder via a sub-mount.

  Si having a width narrower than the width of the light emitting element bar between the light emitting element bar and the light emitting element bar when the light emitting element bars peeled off from the dicing sheet are placed one by one in a jig for end face coating, Japanese Patent Laid-Open No. 10-093187 discloses a technique for reliably forming a light reflecting film on a cleavage surface of a light emitting element bar by inserting a spacer made of InP or GaAs and projecting the cleavage surface of the light emitting element bar from the spacer. ing.

JP-A-10-093187

  In the prior art, as described above, the light emitting element bars are peeled off from the dicing sheet one by one using a tool such as tweezers, and the peeled light emitting element bars one by one are jigs for end face coating. At this time, the light emitting element bar is easily damaged. For this reason, both ends of the light emitting element bar have a work allowance of about 1 mm to 2 mm, and such portions are held with a tool. And finally, both ends are not used. Therefore, material loss occurs. Further, in the method disclosed in the above-mentioned patent publication, a spacer made of Si, InP or GaAs is used, which leads to an increase in manufacturing cost of the semiconductor light emitting device.

  Accordingly, an object of the present invention is to provide a method for manufacturing a semiconductor light-emitting device capable of avoiding material loss as much as possible and capable of forming a light-reflecting film by an inexpensive method, and a light-reflecting film in a light-emitting element bar. It is in providing the formation method.

In order to achieve the above object, a method for manufacturing a semiconductor light emitting device of the present invention includes:
(A) A stacked structure of compound semiconductor layers is formed, and the first and third sides facing each other are parallel to the X direction, and the remaining second and fourth sides are parallel to the Y direction. Prepare the board
(B) The laminated structure is bonded to the support film, and at least the support film protrudes from the second side of the substrate.
(C) Scratch the support film and the substrate parallel to the X direction, and then
(D) cleaving the substrate parallel to the X direction;
(E) After obtaining the light emitting element bar in a state where the support film is bonded by tearing the support film,
(F) Laminating a plurality of light emitting element bars with a support film interposed therebetween, and heating the support film causes the support film to thermally contract at least along the Y direction, thereby causing XZ of the light emitting element bar. A gap is provided along the Y direction between the end surface and the edge of the support film, and then
(G) forming a light reflecting film on each of the two XZ end faces of each light emitting element bar;
Each step is provided.

In order to achieve the above object, a method of forming a light reflecting film in the light emitting element bar of the present invention is as follows.
(A) A stacked structure of compound semiconductor layers is formed on a substrate, and the first and third sides facing each other are parallel to the X direction, and the remaining second and fourth sides are parallel to the Y direction. Prepare a rectangular light emitting element bar,
(B) The laminated structure is bonded to the support film, and at least the support film protrudes from the second side of the light emitting element bar.
(C) Laminating a plurality of light emitting element bars with a support film interposed therebetween, and heating the support film causes the support film to thermally contract at least along the Y direction, thereby causing XZ of the light emitting element bar. A gap is provided along the Y direction between the end surface and the edge of the support film, and then
(D) forming a light reflecting film on each of the two XZ end faces of each light emitting element bar;
Each step is provided.

  In the method for manufacturing a semiconductor light emitting device of the present invention, in step (B), the laminated structure is bonded to a support film so that the support film protrudes from at least the second side of the substrate. In the method for forming a light reflecting film in a light emitting element bar of the present invention, in step (b), the laminated structure is bonded to a support film, and at least the support film protrudes from the second side of the light emitting element bar. It will be in the state. Therefore, in the subsequent steps, the support film protruding from the second side of the substrate may be used as a work allowance, so that material loss can be avoided as much as possible. Further, chipping of the light emitting element bar and scratches on the end surface can be prevented, and high reliability can be obtained. Furthermore, in the method for manufacturing a semiconductor light emitting device of the present invention or the method for forming a light reflecting film in the light emitting element bar of the present invention, the light emitting element bar extends along the Y direction between the XZ end surface of the light emitting element bar and the support film edge. Then, a plurality of light emitting element bars are stacked with a support film interposed therebetween with a gap therebetween, and then a light reflecting film is formed on each of the two XZ end faces of each light emitting element bar. Therefore, as in the prior art, a support film having the same function as a so-called dicing sheet is used. However, since such a support film is also used as a spacer disclosed in JP-A-10-093187, it is simply heated. Since a gap can be provided along the Y direction between the XZ end face of the light emitting element bar and the edge of the support film, the light reflecting film can be formed by an inexpensive method.

1A and 1B are schematic partial cross-sectional views of an element manufacturing substrate and the like for explaining a method for manufacturing a semiconductor light emitting device of Example 1. FIG. 2A and 2B are a schematic view and an XZ plane, respectively, of a substrate and the like for explaining the method for manufacturing the semiconductor light emitting device of Example 1 from above, following FIG. 1B. It is typical sectional drawing when cut | disconnecting by. FIG. 3 is a schematic view of the substrate and the like for explaining the method for manufacturing the semiconductor light emitting device of Example 1 as viewed from above, following FIG. FIG. 4 is a schematic view of the support film for explaining the method for manufacturing the semiconductor light-emitting device of Example 1 as viewed from below, following FIG. FIG. 5 is a schematic view of the substrate and the like for explaining the manufacturing method of the semiconductor light emitting device of Example 1 as viewed from above, following FIG. 6A, 6 </ b> B, and 6 </ b> C are schematic views of a light-emitting element bar for explaining the method of manufacturing the semiconductor light-emitting device of Example 1 from above, following FIG. 5, XZ It is typical sectional drawing when cut | disconnected by a plane, and typical sectional drawing when cut | disconnected by the YZ plane. FIG. 7 is a schematic view of the light emitting element bar / support film laminate as viewed from the Y direction in order to describe the method for manufacturing the semiconductor light emitting device of Example 1, following FIG. FIG. 8 is a schematic view of the light emitting element bar / support film laminate as viewed from the X direction in order to describe the method for manufacturing the semiconductor light emitting device of Example 1, following FIG. FIGS. 9A and 9B are schematic views of the light emitting element bar for explaining the method of manufacturing the semiconductor light emitting device of Example 1, as viewed from above, following FIGS. 7 and 8, respectively. It is typical sectional drawing when cut | disconnecting by a YZ plane. 10A and 10B are schematic views of the light emitting element bar / support film laminate as viewed from the X direction in order to explain the method for manufacturing the semiconductor light emitting device of Example 1. FIG. FIGS. 9A and 9B are a schematic view of the light emitting element bar for explaining the method of manufacturing the semiconductor light emitting device of Example 1, as viewed from above, and a schematic view when cut along the YZ plane, respectively. FIG. 12A and 12B are schematic views of a light emitting element bar for explaining a method for manufacturing the semiconductor light emitting device of Example 2, as viewed from above. FIGS. 13A, 13B, and 13C are schematic views of the light emitting element bar for explaining the method of manufacturing the semiconductor light emitting device of Example 3, as viewed from above, when cut along the XZ plane. It is typical sectional drawing of this, and typical sectional drawing when cut | disconnecting by a YZ plane.

Hereinafter, the present invention will be described based on examples with reference to the drawings. However, the present invention is not limited to the examples, and various numerical values and materials in the examples are examples. The description will be given in the following order. In addition, the method for manufacturing a semiconductor light emitting device of the present invention and the method for forming a light reflecting film in the light emitting element bar of the present invention may be collectively referred to simply as “the method of the present invention”.
1. 1. General description of a method for manufacturing a semiconductor light emitting device of the present invention and a method for forming a light reflecting film in a light emitting element bar of the present invention. Example 1 (Specific Description of Manufacturing Method of Semiconductor Light Emitting Device of the Present Invention)
3. Example 2 (Modification Example of Manufacturing Method of Semiconductor Light Emitting Device of Example 1)
4). Example 3 (Specific Description of Method for Forming Light Reflecting Film in Light Emitting Element Bar of the Present Invention)

[Description of General Method for Manufacturing Semiconductor Light-Emitting Device of the Present Invention and Method for Forming Light Reflecting Film in Light-Emitting Element Bar of Present Invention]
In the manufacturing method of the semiconductor light emitting device of the present invention, following the step (G), and in the method of forming the light reflecting film in the light emitting element bar of the present invention, following the step (e), After the light emitting element bar is cleaved in parallel with the Y direction to obtain a plurality of light emitting element chips, the support film is stretched in the X direction and then the light emitting element chips are removed from the support film. . Thus, a plurality of light emitting element chips can be obtained from one light emitting element bar.

  In the method of the present invention including the preferred embodiment described above, the length of the gap provided along the Y direction between the XZ end face of the light emitting element bar and the edge of the support film only needs to exceed 0 mm. Considering variation in the width of the support film when the support film is torn, the length of the light emitting element bar is at least 5% or more, preferably 10% or more, more preferably 20% or more of the length along the Y direction. It is desirable. The upper limit of the gap length is not particularly limited.

  In the method of the present invention including the above-mentioned preferred forms and configurations, the support film preferably has stretchability along the X direction and has easy tearability in the Y direction. In this case, the elongation percentage along the X direction of the support film is 125% or more, preferably 200% or more. Here, “the support film has tearability in the Y direction” means that a cut is made in the center of one side parallel to the Y direction of the support film having a width of 20 mm along the Y direction, Grip the edge of one side in two places, fix one gripping part, and tear the support film by moving the other gripping part in the direction of 180 degrees with respect to one gripping part at a speed of 1 m / min. This means that the difference between the width value when tearing 20 mm and the width before tearing is 0.5 mm or less.

  In the method of the present invention including the preferred embodiment and configuration described above, the support film is formed of a biaxially stretched polypropylene resin, a biaxially stretched polyester resin, a uniaxially stretched high density polyethylene resin, a uniaxially stretched medium density polyethylene resin, Consists of uniaxially stretched low density polyethylene resin, polyolefin resin, polyamide resin, polyvinyl chloride resin, polyvinylidene chloride resin, or a mixture of these resins, or any of these resins Although it can be configured as a laminate of films, among them, it has excellent heat resistance and directionality (a large difference in strength between the longitudinal and transverse directions of the film and weakness to tearing in the longitudinal direction). It is more preferable to use a polypropylene-based resin or a uniaxially stretched high-density polyethylene-based resin. Furthermore, in the method of the present invention including the preferred modes and configurations described above, it is preferable that a pressure-sensitive adhesive layer or an adhesive layer is formed on one surface of the support film. Here, examples of the material constituting the pressure-sensitive adhesive layer include rubber-based pressure-sensitive adhesives using natural rubber or synthetic rubber as a base polymer, silicone-based pressure-sensitive adhesives, and acrylic-based adhesives based on an acrylic polymer. Examples of the adhesive layer include acrylic resin adhesives, epoxy resins and / or phenol resin adhesives. The method for attaching the laminated structure to the support film may be appropriately determined depending on the material constituting the pressure-sensitive adhesive layer and the adhesive layer. For example, pressure is applied to the pressure-sensitive adhesive layer using a roller or the like. Examples thereof include a method for causing an adhesive layer to exert an adhesive function by ultraviolet rays or heat. Moreover, as a method of peeling a laminated structure from a support film, the method of applying mechanical pressure and peeling, and the method of losing an adhesive function with an ultraviolet-ray or a heat | fever can be mentioned.

  In the method for manufacturing a semiconductor light emitting device of the present invention or the method for forming a light reflecting film in the light emitting element bar of the present invention, a support film is attached to the plurality of light emitting element bars in the step (F) or the step (c). The support film is heat-shrinked at least along the Y direction by laminating with the interposed state and the support film is heated, but after laminating a plurality of light emitting element bars with the support film interposed, the support film is You may heat, and after heating a support film, you may laminate | stack a several light emitting element bar in the state which interposed the support film.

  The manufacturing method of the semiconductor light emitting device of the present invention including the preferred embodiment and configuration described above, or the method of forming a light reflecting film in the light emitting element bar of the present invention including the preferable configuration described above (hereinafter collectively referred to as these). In some cases, the light emitting element bar is composed of a light emitting element array or a light emitting element assembly in which a plurality of light emitting elements are arranged in a row so that the light emission directions are aligned. That is, the light emitting portions of the plurality of light emitting elements are arranged in a line along the X direction. And as a number of light emitting elements, 20, 25, 33, 50, 100 can be mentioned, for example, 100 or more may be mentioned. The length of the light emitting element bar (the length along the direction in which a plurality of light emitting elements are arranged in a row, specifically, the length along the X direction) can be about 10 mm.

In the present invention, as a substrate or an element manufacturing substrate (so-called wafer) on which a laminated structure of compound semiconductor layers is formed, a GaAs substrate, GaP substrate, InP substrate, AlGaN substrate, GaInP substrate, ZnS substrate, sapphire Examples include a substrate, a SiC substrate, an alumina substrate, a ZnO substrate, a LiMgO substrate, a LiGaO ₂ substrate, a MgAl ₂ O ₄ substrate, a Si substrate, and a Ge substrate. Furthermore, those having a buffer layer or an intermediate layer formed on the surface (main surface) of these element manufacturing substrates can be used as the substrate or the element manufacturing substrate. In addition, with respect to the main surface of these element manufacturing substrates, depending on the crystal structure (for example, cubic or hexagonal type), the so-called A plane, B plane, C plane, R plane, M plane, N plane, A crystal orientation plane called by a name such as an S plane, or a plane in which these are turned off in a specific direction can also be used. Note that by cleaving or cutting the element manufacturing substrate, a rectangular substrate having two opposite sides parallel to the X direction and the remaining two sides parallel to the Y direction can be obtained.

  In the method for manufacturing a semiconductor light emitting device of the present invention, in the step (A), the first side and the third side facing each other are parallel to the X direction, and the remaining second side and fourth side are set to the Y direction. A parallel rectangular substrate is prepared. In the method for forming a light reflecting film in the light emitting element bar of the present invention, in step (a), the first side and the third side facing each other are parallel to the X direction, and the remaining second side and A rectangular light emitting element bar having four sides parallel to the Y direction is prepared. Here, the first side and the third side are expressed as being parallel to the X direction. However, in obtaining the first side and the third side, the first side and the third side are caused by variations in the manufacturing process. May not be strictly parallel to the X direction. Similarly, the second side and the fourth side are expressed as being parallel to the Y direction. However, in obtaining the second side and the fourth side, the second side and the fourth side are obtained due to variations in the manufacturing process. May not be strictly parallel to the Y direction. Accordingly, a rectangular substrate is prepared, or a rectangular light emitting element bar is prepared, but a rectangular substrate in a strict sense, a substrate that is not a rectangular light emitting element bar, and a light emitting element bar are prepared. It may be possible.

  The compound semiconductor layer laminated structure in the present invention or each light emitting element constituting the light emitting element bar is, for example, a first compound semiconductor layer having a first conductivity type, an active layer, which is sequentially formed on a substrate. And a first compound electrode composed of a second compound semiconductor layer having a second conductivity type different from the first conductivity type and electrically connected to the first compound semiconductor layer; The second electrode is electrically connected. When the element manufacturing substrate has conductivity, a first compound semiconductor layer, an active layer, and a second compound semiconductor layer are sequentially formed on one surface (main surface) of the element manufacturing substrate. Then, the first electrode may be formed on the other surface of the element manufacturing substrate, and the first electrode may be a common first electrode in the plurality of light emitting elements. On the other hand, the second electrode may be formed on the second compound semiconductor layer, for example. Here, the first conductivity type may be n-type, the second conductivity type may be p-type, the first conductivity type may be p-type, and the second conductivity type may be n-type.

  As various compound semiconductor layers including the active layer, for example, a GaN-based compound semiconductor (including AlGaN mixed crystal, AlGaInN mixed crystal, and GaInN mixed crystal), a GaInNAs-based compound semiconductor (including GaInAs mixed crystal or a GaNAs mixed crystal), AlGaInP-based, etc. Compound semiconductor, AlAs compound semiconductor, AlGaInAs compound semiconductor, AlGaAs compound semiconductor, GaInAs compound semiconductor, GaInAsP compound semiconductor, GaInP compound semiconductor, GaP compound compound semiconductor, InP compound semiconductor, InN compound semiconductor, AlN compound Compound semiconductors can be exemplified. Examples of n-type impurities added to the compound semiconductor layer include silicon (Si), sulfur (S), selenium (Se), tellurium (Te), and tin (Sn). As p-type impurities, Examples include carbon (C), zinc (Zn), magnesium (Mg), and beryllium (Be). The active layer may be composed of a single compound semiconductor layer, or may have a single quantum well structure [QW structure] or a multiple quantum well structure [MQW structure]. As a method for forming various compound semiconductor layers including an active layer (film formation method), metal organic chemical vapor deposition (MOCVD method, MOVPE method), metal organic molecular beam epitaxy method (MOMBE method), halogen transport or reaction Hydride vapor phase epitaxy method (HVPE method) and plasma assisted physical vapor phase epitaxy method (PPD method) which contribute to the above.

  The second compound semiconductor layer in a certain light emitting element and the second compound semiconductor layer in the light emitting element adjacent to the light emitting element need to be electrically separated. In order to achieve this electrical separation, for example, between a certain light emitting element and a light emitting element adjacent to the light emitting element (hereinafter, this portion is referred to as a “border portion of the light emitting element” for convenience) A method of removing a portion of the second compound semiconductor layer in order to spatially separate, and a method of forming (depositing) an insulating layer by removing a portion of the second compound semiconductor layer at a boundary portion of the light emitting element, A method of growing a first compound semiconductor layer by removing a portion of a second compound semiconductor layer at a boundary portion of a light emitting element, an insulating material such as a polyimide resin by removing a portion of the second compound semiconductor layer at a boundary portion of the light emitting element And a method of ion-implanting boron ions or hydrogen ions into the second compound semiconductor layer portion at the boundary portion of the light emitting element.

  When the first electrode or the second electrode is formed on the compound semiconductor layer or substrate having the p-type conductivity type, Au / AuZn, Au / Pt / Ti (/ Au) / AuZn is used as the electrode (p-side electrode). Au / AuPd, Au / Pt / Ti (/ Au) / AuPd, Au / Pt / TiW (/ Ti) (/ Au) / AuPd, Au / Pt / Ti, and Au / Ti. When the first electrode or the second electrode is formed on a compound semiconductor layer or substrate having an n-type conductivity type, Au / Ni / AuGe, Au / Pt / Ti (/ Au) / Ni / AuGe and Au / Pt / TiW (/ Ti) / Ni / AuGe. It should be noted that the layer before “/” is located at a position electrically separated from the active layer.

  The substrate is cleaved in parallel with the X direction, and the cleaving method may be a known method such as using a scribe device. As a method of tearing the support film, for example, a method of pulling a substrate located at the outermost periphery along the Y direction can be exemplified. Further, a method of scribing the support film and the substrate may be a well-known method. Although the support film protrudes from the second side of the substrate or the light emitting element bar, or from the second side and the fourth side, the length of the protruding part of the support film is from the viewpoint of ease of work, What is necessary is just to determine suitably. The heating temperature, time, atmosphere, and heating method of the support film for shrinking the support film are also based on the material constituting the support film, the pressure-sensitive adhesive layer formed on the support film, or the material constituting the adhesive layer, as appropriate. Just decide. In order to stack the plurality of light emitting element bars with the support film interposed, an appropriate jig may be used.

As a method of forming a light reflecting film on each of the two XZ end faces of each light emitting element bar, various vacuum deposition methods and sputtering methods can be exemplified. In general, a light reflecting film formed on one XZ end face (referred to as “XZ rear end face” for convenience) of a light emitting element bar that is a light reflecting face has a high light reflectivity. On the other hand, the light reflecting film formed on the other XZ end face (referred to as “XZ front end face” for convenience) of the light emitting element bar, which is the light emitting face, has a low light reflectivity and passes a considerable proportion of light. Let The light reflectance of the XZ front end face is, for example, around 15%, and the light reflectance of the XZ rear end face is, for example, around 95%. As a light reflecting film formed on the rear end face of XZ, a multilayer structure film of Al ₂ O ₃ film / amorphous silicon film, for example, an Al ₂ O ₃ film having a thickness of 97 nm and an amorphous silicon film having a thickness of 44 nm was repeated three times. A six-layer film can be exemplified, and an Al ₂ O ₃ film (thickness: 130 nm or 265 nm) can be exemplified as a light reflecting film formed on the front end face of XZ.

  A method for preparing the light emitting element bar will be described later.

  The light emitting element bar is often attached to a heat sink. The heat sink may be produced from a metal or alloy such as copper, copper tungsten, copper alloy, iron, stainless steel, aluminum, or aluminum alloy based on machining (for example, cutting). A sub-mount provided with a layer (for example, a layer made of AlN, SiC, or CuW) between the heat sink and the light emitting element bar, for relaxing the difference between the thermal expansion coefficient of the heat sink and the thermal expansion coefficient of the light emitting element bar. May be arranged. In order to attach the light emitting element bar to the heat sink, for example, an electrode provided on the light emitting element bar and a heat sink may be soldered. The second electrode of the light emitting element may be attached to the heat sink, or the first electrode of the light emitting element may be attached to the heat sink. In the former case, the compound semiconductor layer and the substrate are stacked in this order on the heat sink, and the light emitting element bar is attached by the so-called junction down method. On the other hand, in the latter case, the substrate and the compound semiconductor layer are laminated in this order on the electrode block, and the light-emitting element bar is attached by a so-called junction-up method.

  A specific example of the light emitting device in the present invention is a semiconductor laser device. And the light emitting element bar in this invention can be used as a red light source etc. of a laser projector, for example.

  Example 1 relates to a method for manufacturing a semiconductor light emitting device of the present invention.

  In Example 1, an n-GaAs substrate is used as the substrate 40 or as the element manufacturing substrate (wafer) 10 on which the laminated structure (light emitting portion) of the compound semiconductor layers is formed. The laminated structure 20 of compound semiconductor layers, or each light emitting element constituting the light emitting element bar (semiconductor laser bar) 60 is a first conductivity type formed on the substrate 40 (in Example 1). , N-type) first compound semiconductor layer 21, active layer 23, and second compound having a second conductivity type (p-type in Example 1) different from the first conductivity type. The semiconductor layer 22 is configured. A first electrode 31 electrically connected to the first compound semiconductor layer 21 and a second electrode 32 electrically connected to the second compound semiconductor layer 22 are provided. Since the substrate 40 has conductivity, the first compound semiconductor layer 21, the active layer 23, and the second compound semiconductor layer 22 are sequentially formed on one surface (main surface) of the substrate 40. The first electrode 31 is formed on the other surface of the substrate 40. The first electrode 31 is a common first electrode in a plurality of light emitting elements. The first electrode 31 has a structure in which, for example, a gold (Au) -germanium (Ge) alloy layer, a nickel (Ni) layer, and a gold (Au) layer are sequentially stacked from the substrate 40 side. . On the other hand, the second electrode is formed on the second compound semiconductor layer 22. The second electrode 32 includes, for example, a titanium (Ti) layer, a platinum (Pt) layer, a gold (Au) layer, a titanium (Ti) layer, a platinum (Pt) layer, and a gold (Au) layer in this order. Have a laminated structure.

  The compositions of the first compound semiconductor layer 21, the active layer 23, the second compound semiconductor layer 22, etc. are illustrated in Table 1 below.

[Table 1]
Second compound semiconductor layer p-side contact layer: GaAs
Intermediate layer: GaInP
Second p-type cladding layer: AlInP
Etching stop layer: GaInP
First p-type cladding layer: AlInP
Second light guide layer: Al _0.6 Ga _0.4 InP
Active layer Well layer: GaInP
First compound semiconductor layer First light guide layer: Al _0.6 Ga _0.4 InP
n-type cladding layer: AlInP
Buffer layer: GaInP

  Specifically, the light emitting element bar 60 includes a light emitting element array in which light emitting portions of 33 semiconductor laser elements are arranged in a line along the X direction. The light emitting element is composed of, for example, a red light emitting semiconductor laser element having an oscillation wavelength in a wavelength range of 630 nm to 690 nm. The length of the light emitting element bar 60 along the X direction is 10 mm, the resonator length (the length of the light emitting element bar 60 along the Y direction) is 200 μm to 1.5 mm, specifically in Example 1. 0.7 mm. The thickness of the light emitting element bar 60 is about 100 μm.

  In the method for manufacturing the semiconductor light emitting device of Example 1, the support film 50 to be used is made of a biaxially stretched polypropylene resin having a thickness of 50 μm, and a silicone adhesive layer is formed on one surface of the support film 50. . The support film 50 has stretchability along the X direction and easy tearability in the Y direction. Specifically, the elongation percentage along the X direction of the support film 50 is 150%.

  Hereinafter, with reference to FIGS. 1 to 11, a method for manufacturing the semiconductor light emitting device of Example 1 will be described.

[Step-100]
First, a laminated structure (light emitting part) 20 of compound semiconductor layers is formed on the element manufacturing substrate 10. In the following examples, when various compound semiconductor layers are grown by MOCVD, for example, phosphine (PH ₃ ) is used as a phosphorus source, and trimethylgallium (TMG) gas or triethylgallium (TEG) is used as a gallium source. ) Gas, trimethylaluminum (TMA) gas as the aluminum source, trimethylindium (TMI) gas as the In source, monosilane gas (SiH ₄ gas) as the silicon source, and cyclopentadienylmagnesium gas as the Mg source May be used.

  Specifically, the buffer layer 11 is formed on the main surface of an element manufacturing substrate (wafer) 10 made of an n-GaAs substrate based on a normal MOCVD method, that is, an MOCVD method using an organic metal or a hydrogen compound as a source gas. The first compound semiconductor layer 21, the active layer 23, and the second compound semiconductor layer 22 are epitaxially grown. In this way, a structure having a schematic partial cross-sectional view shown in FIG. In the drawing, each of the first compound semiconductor layer 21, the active layer 23, and the second compound semiconductor layer 22 may be shown as a single layer, and the buffer layer 11 may not be shown. The laminated structure 20 may be shown as one layer.

Next, a boundary portion (current confinement region) of the light emitting element is formed. Specifically, the portion of the second compound semiconductor layer 22 at the boundary portion of the light emitting element is removed in a groove shape up to above the etching layer, and the portion of the second compound semiconductor layer 22 removed in the groove shape is subjected to CVD. The insulating layer 24 made of SiO ₂ , SiN, or Al ₂ O ₃ is formed (film formation) by the method. In addition, as a method for forming the boundary portion of the light emitting element, there is another method in which the second compound semiconductor layer portion is removed and spatially separated, and the second compound semiconductor layer portion in the boundary portion of the light emitting element is removed to obtain polyimide. A method of embedding with an insulating material such as a resin, a method of growing a first compound semiconductor layer by removing a portion of the second compound semiconductor layer in a boundary portion of the light emitting element, and a portion of the second compound semiconductor layer in a boundary portion of the light emitting element A method of implanting boron ions or hydrogen ions may be employed. Next, the second electrode 32 is formed on the top surface of the second compound semiconductor layer 22 based on the electron beam evaporation method. On the other hand, the first electrode 31 is formed on the back surface of the element manufacturing substrate 10 whose thickness is reduced by polishing based on the electron beam evaporation method. In this way, a structure having a schematic partial cross-sectional view shown in FIG. 1B can be obtained.

[Step-110]
Next, a stacked structure 20 of compound semiconductor layers is formed, and the first and third sides facing each other are parallel to the X direction, and the remaining second and fourth sides are parallel to the Y direction. A substrate 40 is prepared. Specifically, the substrate 40 can be obtained by cleaving the element manufacturing substrate 10 using a scribe device. The length of the rectangular substrate 40 in the X direction (corresponding to the length of the light emitting element bar) was 10 mm, and the length in the Y direction was 35 mm. 50 light emitting element bars with a width of 0.7 mm were obtained. However, in the drawing, 10 light emitting element bars are displayed in order to simplify the drawing.

[Step-120]
Thereafter, the laminated structure 20 is bonded to the support film 50 so that the support film 50 protrudes from at least the second side 42 of the substrate 40. In Example 1, the support film 50 protruded from the second side 42 and the fourth side 44 of the substrate 40. A view of this state viewed from above (substrate side) is shown in the schematic view of FIG. 2A, and a schematic cross-sectional view of this state cut along the XZ plane is shown in FIG. In order to attach the laminated structure 20 to the support film 50, pressure may be applied to the support film 50 using, for example, a rubber roller while the support film 50 is in contact with the laminated structure 20.

[Step-130]
Next, the support film 50 and the substrate 40 are scribed in parallel with the X direction. Specifically, 49 scribing lines are made on the exposed surface of the substrate 40 along the X direction by a scribing device. The length of the marking line is 0.5 mm and the depth is several μm, for example. Similarly, a scribing line is also made on the support film 50. The length of the marking line is, for example, 1 mm, and the depth is, for example, several μm. A view of this state viewed from above (substrate side) is shown in the schematic view of FIG. 3, and a view of this state viewed from below (supporting film side) is shown in the schematic view of FIG.

[Step-140]
Then, the substrate 40 is cleaved in parallel with the X direction. Specifically, cleavage is performed using a break machine. Specifically, the ceramic jig provided in the break machine is arranged so as to coincide with the marking line provided on the substrate 40 from the support film side, and the support film 50 is pressed to be provided on the substrate 40. The substrate 40 is cleaved starting from the marked line. By repeating this operation 49 times, the substrate 40 can be divided into 50 strips. A view of this state as viewed from above (substrate side) is shown in the schematic diagram of FIG.

[Step-150]
Then, the light emitting element bar (semiconductor laser bar) 60 in a state where the support film 50 is bonded can be obtained by tearing the support film 50. Specifically, the substrate 40 located at the outermost periphery along the Y direction may be pulled in the direction of the arrow shown in FIG. FIG. 6A is a schematic view of the light emitting element bar 60 thus obtained as viewed from above (substrate side). Further, a schematic cross-sectional view when the light emitting element bar 60 is cut along the XZ plane is shown in FIG. 6B, and a schematic cross-sectional view when cut along the YZ plane is shown in FIG. 6C. .

[Step-160]
Next, a plurality of light emitting element bars 60 are stacked with the support film 50 interposed therebetween, and the support film 50 is heated, so that the support film 50 is thermally shrunk at least along the Y direction. A gap is provided along the Y direction between the 60 XZ end faces 61 and 62 and the edge of the support film 50. Specifically, 100 light-emitting element bars 60 are stacked with the support film 50 interposed therebetween, and a pressing plate 51 made of silicon is disposed above and below. Then, the two holding plates 51 are fixed by an appropriate method so that the holding plates 51 and the plurality of light emitting element bars 60 do not move. FIG. 7 shows a schematic diagram of this state viewed from the Y direction, and FIG. 8 shows a schematic diagram viewed from the X direction. Reference numeral 50 ′ is a protective film sandwiched between the upper holding plate 51 and the substrate 40. Here, this state is referred to as a “light emitting element bar / support film laminate” for convenience. Then, the light emitting element bar / support film laminate is carried into an oven and heated at 90 ° C. for 5 minutes, whereby the support film 50 is thermally contracted along the X direction and the Y direction. Thus, a gap having a length of about 0.1 mm can be provided along the Y direction between the XZ end surfaces 61 and 62 of the light emitting element bar 60 and the edge of the support film 50. FIG. 9A is a schematic view of the light emitting element bar 60 viewed from above (substrate side) in this state. 9B shows a schematic cross-sectional view when the light emitting element bar 60 is cut along the XZ plane, and FIG. 9C shows a schematic cross-sectional view when the light-emitting element bar 60 is cut along the YZ plane. . Further, FIG. 10A shows a schematic cross-sectional view of the light emitting element bar / support film laminate in this state as viewed from the X direction.

[Step-170]
Thereafter, light reflecting films 63 and 64 are formed on the two XZ end faces 61 and 62 of each light emitting element bar 60. Specifically, the light emitting element bar / support film laminate is carried out of the oven and carried into a vacuum deposition apparatus. A light reflecting film 63 made of an Al ₂ O ₃ film and having a light reflectance of about 15% is formed on the XZ front end face (light emitting face) 61 of the light emitting element bar 60. On the other hand, the XZ rear surface (light reflecting surface) 62 of the light-emitting element bar 60 comprises a multilayer structure film of the Al ₂ O ₃ film / amorphous silicon film, the light reflectance is deposited a light reflection film 64 of about 95% . A schematic view of the light emitting element bar / support film laminate in this state viewed from the X direction is shown in FIG. A view of the light emitting element bar 60 as viewed from above (substrate side) is shown in the schematic diagram of FIG. Further, FIG. 11B shows a schematic cross-sectional view when the light emitting element bar 60 is cut along the XZ plane, and FIG. 11C shows a schematic cross-sectional view when cut along the YZ plane. Show. Since there is a gap along the Y direction between the XZ end surfaces 61 and 62 of the light emitting element bar 60 and the edge of the support film 50, the light reflecting films 63 and 64 are formed on the XZ end surfaces 61 and 62. However, it is not blocked by the support film 50. In some cases, [Step-160] may be performed in a vacuum deposition apparatus.

[Step-180]
Next, after the light emitting element bar / support film laminate is carried out of the vacuum deposition apparatus, the light emitting element bar / support film laminate is removed from the jig. At this time, since the support film 50 is attached to the light emitting element bar 60, the XZ front end face 61 and the XZ rear end face 62 of the light emitting element bar 60 can be easily distinguished. Specifically, for example, the length of the blank support film 50 at both ends of the light emitting element bar 61 is changed, and the color and pattern of the support film 50 are changed. Accordingly, the operator can easily determine which side is the XZ front end face 61 or the XZ rear end face 62 of the light emitting element bar 60, and the work time and the manufacturing cost can be reduced. Thereafter, the light emitting element bar 60 is peeled off from the support film 50, and the substrate 40 of the light emitting element bar 60 is soldered to the sub-mount. Furthermore, after attaching the sub mount to the base (heat sink), the electrode member is fixed on the base via an insulating plate, one end of the wire is joined to the step of the electrode member, and the other end of the wire is The two electrodes 32 are joined. Thus, the semiconductor light emitting device can be completed.

  In the manufacturing method of the semiconductor light emitting device of Example 1, in [Step-120], the laminated structure 20 was bonded to the support film 50, and the support film 50 protruded from at least the second side 42 of the substrate 40. State. Accordingly, in the subsequent steps, the support film 50 protruding from the second side 42 of the substrate 40 may be used as a work allowance, and therefore it is possible to avoid material loss as much as possible. Specifically, when the length of the light emitting element bar is set to 10 mm, conventionally, the length of the light emitting element bar is set to 13 mm, and both end portions are set to 1.5 mm as work costs. However, in the manufacturing method of the semiconductor light emitting device of Example 1, such material loss does not occur.

  Furthermore, in the method of manufacturing the semiconductor light emitting device of Example 1, a plurality of light emitting element bars 60 are stacked with the support film 50 interposed therebetween, and the XZ end surfaces 61 and 62 of the light emitting element bar 60 and the support film are stacked. The light reflecting films 63 and 64 are formed (deposited) on the two XZ end surfaces 61 and 62 of each light emitting element bar 60 in a state where a gap is provided along the Y direction between the 50 edge portions. Accordingly, the support film 50 having the same function as that of a so-called dicing sheet is used as in the conventional technique. However, since the support film 50 is also used as a kind of spacer, the light emitting element bar 60 is simply heated. Since a gap can be provided along the Y direction between the XZ end surfaces 61 and 62 and the edge of the support film 50, the light reflecting films 63 and 64 can be formed by an inexpensive method.

  The second embodiment is a modification of the method for manufacturing the semiconductor light emitting device of the first embodiment. In Example 2, after [Step-170] of Example 1, the light emitting element bar 60 bonded to the support film 50 is cleaved in parallel with the Y direction. Thereafter, the support film 50 is stretched in the X direction. FIGS. 12A and 12B are schematic views of the light emitting element bar 60 viewed from above (substrate side) in these states. As a result, in the light emitting element bar 60, a gap is generated between the adjacent light emitting element chips 70 in a state of being bonded to the support film 50, and the light emitting element chips 70 are separated. Next, the light emitting element chip 70 can be obtained by removing the light emitting element chip 70 from the support film 50. Thus, a plurality of light emitting element chips 70 can be obtained from one light emitting element bar 60.

  Example 3 relates to a method of forming a light reflecting film in the light emitting element bar of the present invention.

  Hereinafter, with reference to FIG. 13, the formation method of the light reflection film in the light emitting element bar of Example 3 is demonstrated.

[Step-300]
First, the stacked structure 20 of compound semiconductor layers is formed on the substrate 40, the first side 41 and the third side 43 facing each other are parallel to the X direction, and the remaining second side 42 and fourth side 44 are formed. A rectangular light emitting element bar 360 that is parallel to the Y direction is prepared.

  Specifically, in the same manner as in [Step-100] of Example 1, a laminated structure 20 of compound semiconductor layers is formed on the element manufacturing substrate 10. Next, a boundary portion (current confinement region) of the light emitting element is formed, and further, the second electrode 32 and the first electrode 31 are formed.

[Step-310]
Next, in the same manner as in [Step-110] of Example 1, the stacked structure 20 of compound semiconductor layers is formed, the first side and the third side facing each other are parallel to the X direction, and the remaining second side A rectangular substrate 40 whose fourth side is parallel to the Y direction is prepared. Thereafter, a dicing sheet (not shown) is bonded to the laminated structure side of the rectangular substrate 40 based on a known method. Then, the light emitting element bar 360 can be obtained by cleaving the substrate 40 using a scribing device.

[Step-320]
Then, after sticking the board | substrate 40 with the support film 50 and making it the state which the support film 50 protruded from the 2nd edge | side 42 of the light emitting element bar 360 at least, the sheet | seat for dicing is peeled off. The width of the support film 50 (the length in the Y direction) is equal to or less than the length of the light emitting element bar 360 in the Y direction. That is, the end portion of the support film 50 does not protrude from the XZ end surfaces 61 and 62 of the light emitting element bar 360. A view of the light emitting element bar 360 thus obtained as viewed from above (substrate side) is shown in a schematic diagram of FIG. FIG. 13B shows a schematic cross-sectional view when the light emitting element bar 360 is cut along the XZ plane, and FIG. 13C shows a schematic cross-sectional view when the light-emitting element bar 360 is cut along the YZ plane. .

[Step-330]
Next, a plurality of light emitting element bars 360 are laminated with the support film 50 interposed therebetween, and the support film 50 is heated to thermally contract the support film 50 at least along the Y direction. A gap is provided between the XZ end surfaces 61 and 62 of 360 and the edge of the support film 50 along the Y direction. Thereafter, light reflecting films 63 and 64 are formed on the two XZ end faces 61 and 62 of each light emitting element bar 360. Each of the above steps can be the same as [Step-160] to [Step-170] of the first embodiment. Then, the light emitting element bar can be completed by performing the process similar to [Process-180] of Example 1.

  Even in the third embodiment, a plurality of light emitting element chips 70 can be obtained from one light emitting element bar 360 by performing the same process as in the second embodiment.

  As mentioned above, although this invention was demonstrated based on the preferable Example, this invention is not limited to these Examples. The configuration and structure of the light-emitting element bar and the light-emitting element chip described in the examples, the material constituting the light-emitting element bar and the light-emitting element chip, the manufacturing conditions and various numerical values of the light-emitting element bar and the light-emitting element chip are examples, and are changed as appropriate be able to. In the embodiment, the first conductivity type is n-type and the second conductivity type is p-type. Conversely, the first conductivity type may be p-type and the second conductivity type may be n-type.

  In the embodiment, the description has been made by taking the semiconductor laser element having a laminated structure composed of the AlGaInP-based compound semiconductor layer and emitting red light as an example. However, the present invention includes, for example, the AlGaAs-based compound semiconductor layer. The present invention can also be applied to the manufacture of light emitting element bars and light emitting element chips composed of other material systems such as an infrared semiconductor laser element having a laminated structure and a GaN based semiconductor laser element (oscillation wavelength of 400 nm to 500 nm). In addition, in the embodiments, the light emitting element bar provided with the semiconductor laser element array has been described as an example. However, the present invention is not limited to semiconductor light emitting devices such as edge emitting semiconductor light emitting elements and superluminescent diodes. The present invention can also be applied to the manufacture of a semiconductor light emitting device provided with an element.

DESCRIPTION OF SYMBOLS 10 ... Substrate for device manufacturing (wafer), 11 ... Buffer layer, 20 ... Multilayer structure, 21 ... First compound semiconductor layer, 22 ... Second compound semiconductor layer, 23 ... Active layer, 24 ... insulating layer, 31 ... first electrode, 32 ... second electrode, 40 ... substrate, 41 ... first side, 42 ... second side, 43 ... 3rd side, 44 ... 4th side, 50 ... Supporting film, 50 '... Protective film, 51 ... Holding plate, 60, 360 ... Light emitting element bar, 61, 62 ... XZ end face, 63, 64 ... light reflecting film, 70 ... light emitting element chip

Claims (11)

(A) A stacked structure of compound semiconductor layers is formed, and the first and third sides facing each other are parallel to the X direction, and the remaining second and fourth sides are parallel to the Y direction. Prepare the board
(B) The laminated structure is bonded to the support film, and at least the support film protrudes from the second side of the substrate.
(C) Scratch the support film and the substrate parallel to the X direction, and then
(D) cleaving the substrate parallel to the X direction;
(E) After obtaining the light emitting element bar in a state where the support film is bonded by tearing the support film,
(F) Laminating a plurality of light emitting element bars with a support film interposed therebetween, and heating the support film causes the support film to thermally contract at least along the Y direction, thereby causing XZ of the light emitting element bar. A gap is provided along the Y direction between the end surface and the edge of the support film, and then
(G) forming a light reflecting film on each of the two XZ end faces of each light emitting element bar;
A method of manufacturing a semiconductor light emitting device including each step.   Following the step (G), the light emitting element bar is cleaved parallel to the Y direction to obtain a plurality of light emitting element chips, and then the support film is stretched in the X direction, and then the light emitting element chips are removed from the support film. Item 12. A method for manufacturing a semiconductor light emitting device according to Item 1.   The length of the gap provided along the Y direction between the XZ end face of the light emitting element bar and the edge of the support film is at least 10% or more of the length along the Y direction of the light emitting element bar. A method for manufacturing a semiconductor light emitting device according to claim 1.   The method of manufacturing a semiconductor light emitting device according to claim 1, wherein the support film has stretchability along the X direction and has easy tearability in the Y direction.   The method of manufacturing a semiconductor light emitting device according to claim 4, wherein the elongation percentage along the X direction of the support film is 125% or more.   The support film is a biaxially stretched polypropylene resin, a biaxially stretched polyester resin, a uniaxially stretched high density polyethylene resin, a uniaxially stretched medium density polyethylene resin, a uniaxially stretched low density polyethylene resin, a polyolefin resin, a polyamide resin, 2. The semiconductor light emitting device according to claim 1, wherein the semiconductor light emitting device is a laminate of a film made of a polyvinyl chloride resin, a polyvinylidene chloride resin, a mixture of these resins, or a film made of any of these resins. Production method.   The manufacturing method of the semiconductor light-emitting device according to claim 1, wherein an adhesive layer or an adhesive layer is formed on one surface of the support film. (A) A stacked structure of compound semiconductor layers is formed on a substrate, and the first and third sides facing each other are parallel to the X direction, and the remaining second and fourth sides are parallel to the Y direction. Prepare a rectangular light emitting element bar,
(B) The laminated structure is bonded to the support film, and at least the support film protrudes from the second side of the light emitting element bar.
(C) Laminating a plurality of light emitting element bars with a support film interposed therebetween, and heating the support film causes the support film to thermally contract at least along the Y direction, thereby causing XZ of the light emitting element bar. A gap is provided along the Y direction between the end surface and the edge of the support film, and then
(D) forming a light reflecting film on each of the two XZ end faces of each light emitting element bar;
A method of forming a light reflecting film in a light emitting element bar including each step.   The length of the gap provided along the Y direction between the XZ end face of the light emitting element bar and the edge of the support film is at least 10% or more of the length along the Y direction of the light emitting element bar. A method for forming a light reflecting film in the light emitting element bar according to claim 1.   The support film is a biaxially stretched polypropylene resin, a biaxially stretched polyester resin, a uniaxially stretched high density polyethylene resin, a uniaxially stretched medium density polyethylene resin, a uniaxially stretched low density polyethylene resin, a polyolefin resin, a polyamide resin, The light-emitting element bar according to claim 8, wherein the light-emitting element bar is a laminate of a film made of a polyvinyl chloride resin, a polyvinylidene chloride resin, a mixture of these resins, or a film made of any of these resins. Method for forming light reflecting film.   The method for forming a light reflecting film in a light emitting element bar according to claim 8, wherein an adhesive layer or an adhesive layer is formed on one surface of the support film.

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