JP4839497B2 - Semiconductor light emitting device and method for manufacturing semiconductor light emitting device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a semiconductor light emitting device and a manufacturing method thereof, and more particularly to a semiconductor light emitting device using a compound semiconductor substrate such as gallium arsenide having a surface inclined with respect to a crystal plane and a manufacturing method thereof.
[0002]
[Prior art]
2. Description of the Related Art A semiconductor light emitting device (so-called semiconductor laser) is mounted on an optical pickup device used for writing (recording) and reading (reproduction) on an optical recording medium such as a CD (Compact Disk) and a DVD (Digital Versatile disk).
[0003]
FIG. 10 shows a configuration example of this semiconductor light emitting device. The semiconductor light-emitting device shown in this figure is formed on an n-type GaAs (gallium-arsenic) substrate 101 and an n-type AlGaAs (aluminum-gallium-arsenic) layer through a buffer layer (not shown). A multilayer film pattern is formed by sequentially laminating a lower cladding layer 102 of a type, an active layer 103 having a quantum well structure made of AlGaAs, and a p-type upper cladding layer 104 made of AlGaAs. Further, on the upper clad layer 104, a single current injection layer 105 made of p-type GaAs is extended in the depth direction of the drawing so as to be sandwiched between, for example, the insulating regions 106. A current confinement layer (so-called stripe) 103a is formed. Further, by making the end face of the multilayer film pattern at both ends of the current injection layer 105 in the extending direction into a cleavage plane, the active layer 103 has a resonator structure, and the laser beam generated here is resonated and extracted from the cleavage plane. It is supposed to be.
[0004]
In the semiconductor light emitting device having such a configuration, the band gap near the cleavage plane is larger than the band gap in the central region due to the interface state near the cleavage plane of the active layer 103, poor thermal brushing, high light density, and the like. There is a problem that it will be smaller. For this reason, the emitted light generated in the vicinity of the center of the stripe 103a is easily absorbed in the vicinity of the cleavage plane, causing a large amount of heat generation, limiting the maximum oscillation output, and causing end face destruction.
[0005]
Therefore, a so-called window structure has been proposed that raises the band gap in the vicinity of the cleavage plane of the active layer 103. The semiconductor light emitting device having this window structure has a structure in which the cleavage plane side of the multilayer pattern is embedded with a material having a high band gap, or diffuses impurities into the cleavage plane side end of the multilayer pattern, Divided into a structure in which the superlattice structure is broken to increase the band gap.
[0006]
[Problems to be solved by the invention]
However, forming a window structure with such a configuration complicates the process and requires high-precision process technology, which causes an increase in manufacturing cost of semiconductor light-emitting devices and a decrease in yield. It has become.
[0007]
  For example, when forming a semiconductor light emitting device that oscillates red laser light, Zn (zinc) is diffused as an impurity in the active layer near the cleavage plane. However, Zn easily forms a non-light emitting sensor in the active layer, and if it is present in the light emitting region, it causes deterioration and impairs reliability. For this reason, the amount of Zn to be diffused is set so as to increase the band gap in the vicinity of the cleavage plane, but is almost diffused in the central region of the active layer which is the light emitting region.Let meDon't be. Therefore, an advanced process technique for precisely controlling the Zn diffusion region and the diffusion distance is required.
[0008]
SUMMARY OF THE INVENTION An object of the present invention is to provide a semiconductor light emitting device and a method for manufacturing the same, in which a window structure can be easily provided without requiring an advanced process technique.
[0009]
  In order to achieve such an object, the semiconductor light emitting device of the present invention isCrystal orientation [011] or [011 ^- ] 3 to 15 degrees in the directionOn the surface of the substrate made of a compound semiconductor having an inclined surface,Made of AlGaInP or AlGaAsLower cladding layer,Made of AlGaInP, InGaP or AlGaAsActive layer andMade of AlGaInP or AlGaAsA multilayer film pattern in which an upper cladding layer and the like are sequentially laminated is provided, and a single current injection layer is provided on the upper layer, and an epitaxial layer grown on the substrate is formed on the substrate surface.By wet etchingThe present invention is characterized in that a processing region formed by etching and an initial surface region located on both sides of the processing region are provided. In the multilayer pattern, both end portions in the extending direction of the current injection layer are provided on the initial surface region, and the central portion is provided on the processing region.In addition, the emission wavelength of the active layer in the multilayer pattern is longer on the processed region than on the initial surface region..
[0010]
  The method for manufacturing a semiconductor light emitting device of the present invention is a method for manufacturing a semiconductor device having such a configuration, and is characterized in that it is performed as follows. First, a mask pattern is formed on the surface of the substrate, and an epitaxial layer is grown on the exposed surface of the substrate sandwiched between the mask patterns. Next, the epitaxial layerBy wet etchingEtching is performed to form a processed region on the surface of the substrate, and the mask pattern is removed to expose the initial surface region of the substrate on both sides of the processed region. Thereafter, a multilayer film is formed on the substrate, and a current injection layer extending over the processing region and extending to the initial surface region on both sides is formed thereon.
[0011]
In the semiconductor light emitting device having such a configuration, the central portion of the stripe in the active layer formed along the current injection layer is constituted by the active layer portion of the multilayer film pattern formed on the processing region, and the stripe Both end portions are constituted by the active layer portions of the multilayer film pattern formed on the initial surface region. Here, as shown in the graph of FIG. 5, the light emission in the active layer in the multilayer film formed on the processed region is compared with the light emission wavelength λb in the active layer in the multilayer film formed on the initial surface region. It has been experimentally found that the wavelength λa becomes longer. Therefore, in the stripe of this semiconductor light emitting device, the light emission wavelength at the central portion formed on the processing region is long (that is, the band gap is small), and the light emission at both end portions formed on the initial surface region 1b. The wavelength is short (that is, the band gap is large). Therefore, this semiconductor light emitting device has a window structure.
[0012]
In the manufacturing method of the present invention, since the current injection layer is formed on the multilayer film so as to extend on the both sides of the initial surface region across the processing region, the current injection layer is formed on the initial surface region. By patterning (cleaving) the current injection layer and the multilayer film so as to cross the extending direction of the semiconductor light emitting device, a semiconductor light emitting device in which the extending direction end of the current injection layer is provided on the initial surface region can be obtained. Therefore, a semiconductor light-emitting device having the above-described window structure can be obtained only by adding simple steps such as mask pattern formation, epitaxial layer formation, and etching removal.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of a semiconductor light emitting device and a method for manufacturing the same according to the present invention will be described in detail with reference to the drawings.
[0014]
(First embodiment)
1 to 4 are diagrams for explaining a first embodiment of the present invention. Hereinafter, the manufacturing method will be described in order with reference to these drawings.
[0015]
First, as shown in FIG. 1A, an n-type substrate 1 made of a compound semiconductor such as GaAs is prepared. The substrate 1 is a so-called OFF substrate having a surface having an inclination angle (OFF angle) with respect to the crystal plane of GaAs. Here, the (001) plane of GaAs is aligned with the crystal orientation [011] or [011]^-] {However, (-) is a logical negation signifying inversion} An OFF substrate having a surface with an OFF angle of about 3 to 15 degrees, preferably 10 degrees in the direction is used. .
[0016]
Then, a mask pattern 2 made of a silicon oxide material or a silicon nitride material is formed on the surface of the substrate 1. The mask pattern 2 is provided so as to extend in a direction perpendicular to the stripe of the semiconductor light emitting device formed here, and the silicon oxide film or the silicon nitride film formed on the substrate 1 is patterned. To be formed. Here, the stripe of the semiconductor light emitting device is extended in a direction perpendicular to the direction of inclination of the crystal orientation of the substrate 1. Therefore, the mask pattern 2 is extended in the tilt direction of the crystal orientation of the substrate 1.
[0017]
Next, as shown in FIG. 1B, several μm is selectively formed on the exposed surface of the substrate 1 by an epitaxial growth method such as metal organic vapor phase epitaxy (MOVPE). An epitaxial layer 3 having a thickness is grown. The epitaxial layer 3 may be a material layer that can be epitaxially grown on the substrate 1, such as GaAs, AlGaAs, or AlGaInP (aluminum-gallium-indium-phosphorus).
[0018]
Thereafter, as shown in FIG. 1 (3), the surface of the substrate 1 is exposed by etching away the epitaxial layer (3) formed in the previous step, whereby the epitaxial layer is etched away on the surface of the substrate 1. The processing area 1a is formed. At this time, when the epitaxial layer (3) is made of AlGaAs or AlGaInP, selective etching using, for example, a sulfuric acid-based etching solution or a hydrofluoric acid-based etching solution is performed. When the epitaxial layer (3) is made of p-type GaAs, selective etching using a potassium ferricyanide / potassium hydroxide solution as an etching solution is performed. Furthermore, in the case where the epitaxial layer (3) is made of n-type GaAs, etching is performed with an etching time controlled using an ammonia-based etchant.
[0019]
Next, as shown in FIG. 1 (4), the mask pattern (2) is etched away from the surface of the substrate 1 to expose the initial surface region 1 b on the surface of the substrate 1. When the mask pattern is made of silicon oxide and a hydrofluoric acid-based etchant is used for etching removal of the epitaxial layer, the mask pattern is simultaneously etched away in the etching removal process of the epitaxial layer.
[0020]
As described above, as shown in the plan view of FIG. 2, on the surface of the substrate 1, the processed region 1 a obtained by etching removal of the epitaxial layer (3) and the initial surface region protected by the mask pattern (2). 1b are alternately arranged. The A-A ′ cross section in FIG. 2 corresponds to FIG.
[0021]
Here, a region indicated by a two-dot chain line a in FIG. 2 is a region corresponding to one conductor light emitting device formed in the following steps that are subsequently performed. The stripe planned portion b of the semiconductor light emitting device is arranged in a direction intersecting with the extending direction of the processing region 1a and the initial surface region 1b. In addition, an extension line of the arrow c in the figure, that is, the vicinity of the center of the initial surface region 1b will be an end face of the semiconductor light emitting device, that is, a cleavage plane in the future.
[0022]
After the above, on the substrate 1 having the processing region 1a and the initial surface region 1b, for example, a buffer layer in which n-type GaAs and n-type InGaP (indium-gallium-phosphorus) (not shown here) are sequentially laminated is formed. Form. Then, as shown in FIG. 3 (corresponding to the AA ′ cross section in FIG. 2) and FIG. 4 (corresponding to the BB ′ cross section in FIG. 2), through the buffer layer (not shown), On the substrate 1, for example, an n-type lower cladding layer 5 made of AlGaInP, an active layer 6 having a quantum well structure (emission wavelength region 650 nm band) made of a single layer or multiple layers of AlGaInP (or InGaP), and a p-type made of AlGaInP. A multilayer film is formed by sequentially laminating the upper cladding layer 7 and the p-type cap layer 8 made of GaAs. If necessary, a guide layer having an intermediate composition is provided between the lower clad layer 5 and the active layer 6, and a guide layer having an intermediate composition is provided between the active layer 6 and the upper clad layer 7. Will be provided. Further, these layers are formed by an epitaxial growth method such as MOVPE.
[0023]
Next, impurities are introduced by ion implantation from the surface of the cap layer 8 to a depth in the middle of the p-type cladding layer 7 with the resist pattern protecting the portion to be the current injection layer 8 a of the cap layer 8. Thus, an insulating region 9 is formed in the impurity introduction portion, and a current injection layer 8a formed by patterning the cap layer 8 is formed. A plurality of the current injection layers 8a are provided along the planned stripe portion b shown in FIG. 2, whereby a single stripe 6a is formed in the active layer 6 of each semiconductor light emitting device region a (see FIG. 2). Is done. The stripe 6a is extended in a direction intersecting with the extending direction of the processing region 1a on the surface of the substrate 1 and the initial surface region 1b.
[0024]
After the above, although illustration is omitted here, a p-type electrode such as Ti (titanium) / Pt (platinum) / Au (gold) is formed in a state of being connected to the current injection layer 8a, and further n-type. An n-type electrode such as AuGe (gold-germanium) / Ni (nickel) / Au (gold) is formed while being connected to the substrate 1. In addition, in the state where the plurality of current injection layers 8a formed on the substrate 1 are divided into single stripes, the electrodes and the layers 5 to 7 are patterned and the substrate 1 is separated and divided.
[0025]
Next, at each cleavage line c in the center of the initial surface region 1b, the substrate 1 and its upper portion are cleaved in the direction intersecting with the extending direction of the current injection layer (8a) and the stripe (6a), and the layers 5 to 7 are patterned. A multilayer film pattern P is formed, thereby completing each semiconductor light emitting device made of an AlGaInP-based quaternary material.
[0026]
The semiconductor light emitting device obtained in this way is such that the vicinity of the cleavage plane, which is the both ends of the stripe 6a, is formed on the initial surface region 1b, and the vicinity of the center is formed on the processing region 1a.
[0027]
Here, FIG. 5 shows the measurement result of the emission wavelength of the photoluminescence in the active layer 6 in the multilayer film (5 to 7) of each AlGaInP-based semiconductor light-emitting device similar to the first embodiment. In this figure, part A shows the emission wavelength of each part of the active layer in the multilayer film directly formed on the processing region. Moreover, B part shows the light emission wavelength of each part of the active layer in the multilayer film on the epitaxial layer left adjacent to the processing region.
[0028]
As shown in this figure, the emission wavelength λa of the active layer in the multilayer film (A part) formed on the processing region is about 666 nm. It can be seen that this is a value about 10 nm larger than the emission wavelength λb = 656 nm in the multilayer film formed on the initial surface region of the substrate. That is, a multilayer film having a longer emission wavelength and a smaller band gap than that on the initial surface region is formed on the processed region.
[0029]
Therefore, in the stripe 6a of the semiconductor light emitting device of the first embodiment, the light emission wavelength at the center portion formed on the processed region 1a is long (that is, the band gap is small), and is formed on the initial surface region 1b. The emission wavelengths at both ends are short (that is, the band gap is large). Therefore, this semiconductor light emitting device has a window structure.
[0030]
That is, according to the first embodiment, without adding a high-precision process, only a simple process such as formation of a mask pattern by rough alignment, formation of an epitaxial layer, and removal of these etchings is performed. Thus, a semiconductor light emitting device having a window structure can be obtained.
[0031]
In the first embodiment, all of the epitaxial layer 3 formed in FIG. 1B is removed by etching. However, the epitaxial layer 3 may be partially left and etched. For example, as shown in FIG. 6, the epitaxial layer 3 may be left on the substrate 1 on both sides of the planned stripe portion b. In this case, by removing the portion of the epitaxial layer 3 on the vicinity of the planned cleavage line c, it becomes easy to recognize the cleavage site in the subsequent cleavage step.
[0032]
(Second Embodiment)
7 to 8 are diagrams for explaining a second embodiment of the present invention. Here, embodiments in which the present invention is applied to a semiconductor light emitting device in which semiconductor lasers having different wavelengths (first laser and second laser) are mounted on one chip will be described in order from the manufacturing method. In addition, the cross-sectional view in each figure becomes an A-A 'cross section in the plan view. The same parts as those in the first embodiment are denoted by the same reference numerals for description.
[0033]
First, as shown in FIG. 7A, an OFF substrate (substrate) 1 made of n-type GaAs similar to the first embodiment is prepared, and a silicon oxide material or silicon nitride is formed on the surface of the substrate 1. A mask pattern 2 ′ (shown only in a plan view) made of a system material is formed. Here, when a region indicated by a two-dot chain line a in the drawing is a region corresponding to one semiconductor light emitting device formed in the following process, the semiconductor light emitting device region a includes the semiconductor light emitting device region a. Two stripe planned portions b and a pair of mask patterns 2 'are arranged. These mask patterns 2 ′ are provided at both ends of the semiconductor light emitting device region “a” at a predetermined interval on a portion where one of the two stripe planned portions “b” is disposed. The mask pattern 2 ′ is formed by patterning a silicon oxide film or a silicon nitride film formed on the substrate 1.
[0034]
Next, an epitaxial layer 3 ′ made of n-type AlGaAs is selectively grown on the exposed surface of the substrate 1 by an epitaxial growth method such as MOVPE. The epitaxial layer 3 ′ also serves as the first lower cladding layer, and may have a laminated structure in which a buffer layer made of n-type AlGaAs is epitaxially grown on an n-type AlGaAs base as necessary.
[0035]
Thereafter, as shown in FIG. 7B, a single layer or multiple layers are formed on the substrate 1 by an epitaxial growth method such as MOVPE in a state of covering the mask pattern 2 ′ (shown only in the plan view) and the epitaxial layer 3 ′. The first active layer 16 having a quantum well structure (oscillation wavelength of 780 nm band) made of AlGaAs, the p-type first upper cladding layer 17 made of AlGaAs, and the p-type first cap layer 18 made of GaAs are sequentially laminated. If necessary, a guide layer having an intermediate composition is provided between the epitaxial layer 3 ′ and the first active layer 16, and between the first active layer 16 and the first upper cladding layer 17, these are provided. A guide layer having an intermediate composition is provided.
[0036]
Next, as shown in 7 (3), a resist pattern (not shown) is formed on the region to be left as the first laser, and sulfuric acid-based non-selective etching using this as a mask and hydrofluoric acid-based AlGaAs selection. By wet etching such as etching, the layers from the first cap layer 18 to the epitaxial layer 3 ′ and the mask pattern (2 ′) are removed by etching in regions other than the first laser region. Thus, the first multilayer film pattern P1 using a ternary material such as AlGaAs is formed.
[0037]
The first multilayer film pattern P1 is provided in a state in which one stripe arranged on the mask pattern (2 ') of the two stripe planned portions b arranged in the semiconductor light emitting device region is exposed.
[0038]
As a result, the surface of the substrate 1 in the region where the second laser is formed is exposed. At this time, on the exposed surface of the substrate 1, a processed region 1a obtained by etching removal of the epitaxial layer (3 ′) and an initial surface region 1b protected by the mask pattern (2 ′) (shown only in the plan view). ) Are alternately arranged along the extending direction of the stripe planned portion b.
[0039]
Next, an n-type buffer layer (not shown) is formed by laminating InGaP on GaAs so as to cover the first multilayer film pattern P1. Next, as shown in FIG. 8A, an n-type second lower cladding layer 25 made of, for example, AlGaInP, and a single-layer or multi-layer AlGaInP (or InGaP) are formed on the substrate 1 through this buffer layer. A quaternary material is formed by sequentially laminating a second active layer 26 having a quantum well structure (oscillation wavelength band of 650 nm), a p-type second upper cladding layer 27 made of AlGaInP, and a p-type second cap layer 28 made of GaAs. A second multilayer film using the above (hereinafter, only shown in the sectional view) is formed. Further, if necessary, a guide layer having an intermediate composition is provided between the second lower cladding layer 25 and the second active layer 26, and between the second active layer 26 and the second upper cladding layer 27. Is provided with a guide layer having an intermediate composition. These layers are formed by an epitaxial growth method such as the MOVPE method.
[0040]
Thereafter, a resist pattern (not shown) is formed on the region of the second multilayer film to be left as the second laser, and sulfuric acid-based cap etching, phosphoric acid-based quaternary selective etching, hydrochloric acid-based using this as a mask. The second multilayer film portion other than the second laser region is etched away by wet etching such as isolation etching. Thus, the second multilayer film pattern P2 separated from the first multilayer film pattern P1 is formed between the first multilayer film patterns P1.
[0041]
Next, as shown in FIG. 8 (2), the first cap layer 18 is protected in a state where the portions of the first multilayer film pattern P1 and the second multilayer pattern P2 serving as current injection regions are protected by a resist pattern (not shown). Impurities are introduced by ion implantation from the surface of the second cap layer 28 to a depth in the middle of the first upper cladding layer 17 and the second upper cladding layer 27. Thus, the insulating regions 19 and 29 are formed in the impurity introduction portion, the first current injection layer 18a formed by patterning the first cap layer 18, and the second current injection layer formed by patterning the second cap layer 28. 28a is formed. These current injection layers 18a and 28a are provided along the planned stripe portion b shown in FIG. 7 (1), whereby a single stripe 16a is formed in the first active layer 16 and the second active layer 16a is formed. A stripe 26a is formed in the layer 26. These stripes 16a and 26a are extended in a direction that alternately crosses the processing region 1a on the surface of the substrate 1 and the initial surface region (1b). In particular, the stripes 26a in the second active layer 26 extend so as to alternately cross the processed region 1a and the initial surface region (1b).
[0042]
After the above, although illustration is omitted here, as in the first embodiment, a p-type electrode such as Ti / Pt / Au is formed in a state of being connected to the current injection layers 8a and 18a, and n An n-type electrode such as AuGe / Ni / Au is formed in a state of being connected to the mold substrate 1.
[0043]
Next, the substrate 1 is divided by combining the first multilayer pattern P1 and the second multilayer pattern P2 that are provided adjacent to each other.
[0044]
Thereafter, as shown in FIG. 9 corresponding to the BB ′ cross section of FIG. 8B, the center of the initial surface region 1b (see FIG. 2) intersects with the extending direction of the current injection layers 18a and 28a. At the cleavage line c that passes, the substrate 1, the second multilayer film pattern P2, and the first multilayer film pattern (P1) not shown here are cleaved to complete each semiconductor light emitting device.
[0045]
The semiconductor light-emitting device thus obtained has a composition in which the first laser including the first active layer 16 and the first active layer 16 are composed as shown in the cross-sectional view of FIG. And a second laser having the second active layer 26 having different wavelengths.
[0046]
Here, in particular, the second laser is formed in the vicinity of the cleaved surface on both ends of the stripe 26a in the second active layer 26 on the initial surface region 1b and in the vicinity of the center on the processing region 1a. . For this reason, the second laser has a window structure as in the semiconductor light emitting device of the first embodiment.
[0047]
Therefore, according to the second embodiment, a simple process such as formation of a mask pattern by rough alignment, formation of an epitaxial layer, and removal of these etchings is added without adding a highly accurate process. Thus, a two-wavelength semiconductor light emitting device in which the window structure is provided in the second laser can be obtained. In addition, by providing a window structure in a quaternary (AlGaInP) second laser that is difficult to extract stable emitted light, it is possible to obtain stable emitted light from the second laser.
[0048]
In the second embodiment, the first multilayer film pattern P1 constituting the first laser and the second multilayer film pattern P2 constituting the second laser are shown as linear line patterns having a constant width. . However, the shape of these patterns P1 and P2 is not limited to a linear line pattern, and a narrow neck portion or the like may be formed as necessary.
[0049]
In the second embodiment, the case where the present invention is applied to a two-wavelength semiconductor light emitting device has been described. However, the present invention is not limited to a semiconductor device in which a plurality of semiconductor lasers having the same wavelength are mounted, an array laser, The same effect can be obtained with the composite laser.
[0050]
Further, in each of the above embodiments, the case where an OFF substrate made of GaAs is used is exemplified, but the present invention is not limited to this, and an OFF made of another compound semiconductor, for example, gallium nitride (GaN). The present invention can also be applied when a substrate is used, and the same effect can be obtained. In this case, however, the materials such as the cladding layer and the active layer and the etching solution used for the patterning are appropriately selected.
[0051]
【The invention's effect】
As described above, according to the semiconductor light emitting device and the method of manufacturing the same of the present invention, the processing region formed by etching and removing the epitaxial layer is provided on the surface of the OFF substrate, the initial surface regions are disposed on both sides thereof, and the stripes are formed above the processing region. By adopting a configuration in which the vicinity of the center is arranged, a simple process such as mask pattern formation by rough alignment, formation of an epitaxial layer, and further etching removal without adding a high-precision process. It becomes possible to obtain a semiconductor light emitting device having a window structure only by adding the above. As a result, the yield of the semiconductor light emitting device having the window structure can be improved and the manufacturing cost can be reduced.
[Brief description of the drawings]
FIG. 1 is a sectional process diagram for explaining a first embodiment.
FIG. 2 is a plan view for explaining the first embodiment.
FIG. 3 is a sectional view (No. 1) for explaining the first embodiment;
FIG. 4 is a sectional view (No. 2) for explaining the first embodiment;
FIG. 5 is a diagram illustrating the effect of the present invention.
FIG. 6 is a plan view showing a modification of the first embodiment.
FIG. 7 is a process diagram (part 1) for explaining the second embodiment;
FIG. 8 is a process diagram (part 2) for describing the second embodiment;
FIG. 9 is a cross-sectional view for explaining a second embodiment.
FIG. 10 is a cross-sectional view illustrating an example of a conventional semiconductor light emitting device.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Substrate, 1a ... Processing area, 1b ... Initial surface area, 2, 2 '... Mask pattern, 3, 3' ... Epitaxial layer, 5 ... Lower clad layer, 6 ... Active layer, 7 ... Upper clad layer, 8a ... Current injection layer, 16 ... first active layer, 17 ... first upper cladding layer, 18a ... first current injection layer, 25 ... second lower cladding layer, 26 ... second active layer, 27 ... second upper cladding layer, 28a ... second current injection layer, P ... multilayer film pattern, P1 ... first multilayer film pattern, P2 ... second multilayer film pattern

Claims (6)

A substrate made of a compound semiconductor having a surface inclined by about 3 to 15 degrees in the crystal orientation [011] or [011 ⁻ ] direction with respect to the crystal plane;
A lower cladding layer made of AlGaInP or AlGaAs, AlGaInP, made of InGaP or active layer and AlGaInP or AlGaAs consisting AlGaAs, and the multilayer film pattern of the lower clad layer and the different conductivity-type upper cladding layer are sequentially stacked on the substrate ,
In a semiconductor light emitting device comprising a single current injection layer provided on the multilayer film pattern,
The surface of the substrate includes a processing region formed by etching is removed by wet etching an epitaxial layer grown on the substrate, and an initial surface area that is located on both sides of the machining area,
The multilayer film pattern, the both end portions of the extending direction of the current injection layer is provided on the initial surface area, Rutotomoni central portion is provided on the processing region, in the active layer in the multilayer film pattern The semiconductor light emitting device having a longer emission wavelength on the processed region than on the initial surface region . On said substrate at both sides of the front SL current injection layer, the epitaxial layer that are left
The semiconductor light emitting device of 請 Motomeko 1 wherein. The pre-Symbol epitaxial layer and the second lower cladding layer, a second active layer of said different composition than the active layer to the upper, second upper cladding layer of a different conductivity type and said epitaxial layer are sequentially stacked 2 multilayer film patterns;
A second current injection layer provided on the second multilayer film pattern in parallel with the current injection layer .
The semiconductor light emitting device of 請 Motomeko 2 wherein. Crystal orientation with respect to the crystal plane [011] or [011 ^-] a mask pattern is formed from three times on the surface of a substrate made of a compound semiconductor having a 15 degrees tilt is allowed surface direction, sandwiched by the mask pattern a step of growing an epitaxial layer on the exposed surface of the substrate that has been,
By removing the etching by wet etching the epitaxial layer, and forming a processed region formed by the epitaxial layer on the surface of the substrate is removed by etching,
Exposing an initial surface region of the substrate on both sides of the processing region by removing the mask pattern;
A multilayer film in which a lower clad layer made of AlGaInP or AlGaAs, an active layer made of AlGaInP, InGaP or AlGaAs, and an upper clad layer made of AlGaInP or AlGaAs and having a conductivity type different from the lower clad layer are sequentially formed on the substrate. And a process of
On the multilayer film, intends rows and step, to form a current injection layer which extends up to both sides of the initial surface region of the processing region in a state of crossing the working area above
Method of manufacturing a semi-conductor light emitting device. In the step of etching away the previous SL epitaxial layer, to remaining the epitaxial layer in the areas of both sides of the current injection layer
The method of manufacturing a semiconductor light-emitting device of 請 Motomeko 4 wherein. Forming a pair of mask patterns on the surface of the substrate made of a compound semiconductor having a surface inclined by about 3 to 15 degrees in the crystal orientation [011] or [011 ⁻ ] direction with respect to the crystal plane;
The mask pattern is formed on the substrate made of AlGaInP or AlGaAs, an epitaxial layer serving as the first lower cladding layer, AlGaInP, InGaP or the first active layer made of AlGaAs, made of AlGaInP or AlGaAs, and said epitaxial layer Forming a first multilayer film in which first upper cladding layers of different conductivity types are sequentially stacked;
By etching away the first multilayer film by wet etching between the mask pattern and on the mask pattern, the epitaxial layer removed by etching the surface of the substrate between the mask pattern to form a first multilayer film pattern Forming a processed region, and
Exposing an initial surface region of the substrate on both sides of the processing region by removing the mask pattern;
A second lower cladding layer made of AlGaInP or AlGaAs on the substrate; a second active layer made of AlGaInP, InGaP or AlGaAs, and having a composition different from that of the first active layer; and the second lower cladding layer made of AlGaInP or AlGaAs. Forming a second multilayer film in which a second upper clad layer of a different conductivity type is laminated,
Forming a second multilayer film pattern by the initial surface area and on the second multilayer film removed by etching on the processing the leaving said second multilayer film in a region first multilayer pattern,
Forming a current injection layer on the first multilayer pattern and the second multilayer film pattern, extending across the initial surface region on both sides of the processing region in a state of crossing the processing region; A method for manufacturing a semiconductor light emitting device.

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