JP2009212179A - Semiconductor laser element and method of manufacturing semiconductor laser element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a semiconductor laser element and a method of manufacturing the semiconductor laser element, for preventing the increase of manufacture processes while preventing the interruption of a part of laser beams by a support substrate and eliminating the need of bonding a semiconductor device part and the support substrate with high positioning accuracy. <P>SOLUTION: The nitride semiconductor laser element 100 (semiconductor laser element) includes the support substrate 10 provided with a cleavage surface 12 and the semiconductor device part 30 bonded to the support substrate 10, and an angle formed by the cleavage surface 12 on the light emitting direction side of the support substrate 10 and a bonding surface 11 to the semiconductor device part 30 of the support substrate 10 is an obtuse angle. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a semiconductor laser element and a method for manufacturing the semiconductor laser element, and more particularly to a semiconductor laser element having a semiconductor element portion bonded to a support substrate and a method for manufacturing the semiconductor laser element.

  Conventionally, a semiconductor laser element having a semiconductor element portion bonded to a support substrate and a method for manufacturing the semiconductor laser element are known (see, for example, Patent Document 1).

  Patent Document 1 discloses a semiconductor laser device including a holding substrate (supporting substrate) and a nitride multilayer body (semiconductor element portion) bonded to the holding substrate. In this semiconductor laser device, a cutting portion is provided on the joint surface of the holding substrate with respect to the nitride multilayer body, and a light emitting portion of the nitride multilayer body is disposed in the vicinity of the cutting portion of the holding substrate, thereby having a predetermined radiation angle. It is possible to suppress a part of the laser light from being blocked by the holding substrate.

JP 2002-299739 A

  However, in the semiconductor laser device described in Patent Document 1, a process for forming a cutting portion on the holding substrate (supporting substrate) is required in addition to the step of cleaving the holding substrate. There is a problem of increasing. In addition, since the light emitting portion of the nitride multilayer body (semiconductor element portion) is disposed in the vicinity of the cutting portion of the holding substrate, it is necessary to perform positioning with high accuracy when the nitride multilayer body and the holding substrate are joined. There is a problem.

  The present invention has been made to solve the above-described problems, and one object of the present invention is to increase the number of manufacturing steps while suppressing a part of the laser light from being blocked by the support substrate. It is an object of the present invention to provide a semiconductor laser element and a method for manufacturing the semiconductor laser element, in which the semiconductor element portion and the support substrate need not be bonded with high positioning accuracy.

Means for Solving the Problems and Effects of the Invention

  In order to achieve the above object, a semiconductor laser device according to a first aspect of the present invention comprises a support substrate having a cleavage plane and a semiconductor element portion bonded to the support substrate, on the light emission direction side of the support substrate. The angle formed between the cleavage plane and the bonding surface of the support substrate with respect to the semiconductor element portion is an obtuse angle. In the present invention, the light emission direction side is a direction side in which laser light having a relatively high light intensity is emitted from the laser light emitted from the pair of resonator surfaces.

  In the semiconductor laser device according to the first aspect of the present invention, as described above, the support substrate is formed so that the angle formed between the cleavage surface of the support substrate on the light emitting direction side and the bonding surface of the support substrate with respect to the semiconductor element portion becomes an obtuse angle. By configuring the structure, the angle between the cleavage surface on the light emitting direction side of the support substrate and the bonding surface of the support substrate with respect to the semiconductor element portion is perpendicular to that on the semiconductor element portion side of the cleavage surface of the support substrate. Since the portion can be further separated from the laser light having a predetermined radiation angle, it is possible to suppress a part of the laser light from being blocked by the support substrate. Thereby, since it is not necessary to provide a cutting part etc. in a support substrate so that a part of laser beam may not be interrupted, it can suppress that a manufacturing process increases. In addition, since it is not necessary to arrange the light emitting portion of the semiconductor element portion in accordance with the cutting portion of the support substrate, it is not necessary to join the semiconductor element portion and the support substrate with high positioning accuracy.

  In the semiconductor laser device according to the first aspect, preferably, the bonding surface of the support substrate to the semiconductor element portion is inclined at a predetermined angle from the crystal plane of the support substrate. With this configuration, the support substrate can be easily cleaved along the crystal plane so as to be inclined at a predetermined angle with respect to the bonding surface of the support substrate with respect to the semiconductor element portion. The support substrate can be easily formed so that the angle formed by the side cleavage surface and the bonding surface of the support substrate with respect to the semiconductor element portion becomes an obtuse angle. As a result, it is possible to easily prevent a part of the laser light from being blocked by the support substrate.

  In the semiconductor laser device according to the first aspect, preferably, the end portion of the cleavage surface on the light emitting direction side of the support substrate on the semiconductor element portion side is behind the light emitting surface of the semiconductor element portion with respect to the light emitting direction. Is arranged. According to this structure, the cleavage surface of the support substrate can be further separated from the laser light, and therefore, it is possible to further suppress a part of the laser light from being blocked by the support substrate.

  In the semiconductor laser device according to the first aspect, preferably, the support substrate and the semiconductor element portion are bonded via an adhesive layer. If comprised in this way, a support substrate and a semiconductor element part can be easily joined by a contact bonding layer.

  In the semiconductor laser device according to the first aspect, the semiconductor element portion is preferably made of a nitride semiconductor. If comprised in this way, the nitride-type semiconductor laser element which can suppress that a part of laser beam will be interrupted | blocked with a support substrate can be obtained.

  In the semiconductor laser device according to the first aspect, the support substrate preferably has conductivity. If comprised in this way, a semiconductor element part can be connected to an electrode via a support substrate.

  A method of manufacturing a semiconductor laser device according to a second aspect of the present invention includes a step of growing a semiconductor element portion on a growth substrate, a bonding surface of a support substrate having a bonding surface inclined at a predetermined angle from a crystal plane, and the semiconductor element portion And cleaving both the semiconductor element portion and the support substrate so that the angle formed between the cleavage surface of the support substrate on the light emission direction side and the bonding surface of the support substrate with respect to the semiconductor element portion becomes an obtuse angle. With.

  In the method of manufacturing the semiconductor laser device according to the second aspect of the present invention, as described above, the step of bonding the bonding surface of the support substrate having the bonding surface inclined at a predetermined angle from the crystal plane and the semiconductor element portion; A step of cleaving both the semiconductor element portion and the support substrate so that an angle formed between the cleavage surface on the light emission direction side of the substrate and the bonding surface of the support substrate with respect to the semiconductor element portion becomes an obtuse angle. Compared with the case where the angle formed between the cleavage surface on the light emission direction side and the bonding surface of the support substrate with respect to the semiconductor element portion is a right angle, the portion on the semiconductor element portion side of the cleavage surface on the light emission direction side of the support substrate is Therefore, it is possible to prevent a part of the laser light from being blocked by the support substrate. Thereby, since it is not necessary to provide a cutting part etc. in a support substrate so that a part of laser beam may not be interrupted, it can suppress that a manufacturing process increases. In addition, since it is not necessary to arrange the light emitting portion of the semiconductor element portion in accordance with the cutting portion of the support substrate, it is not necessary to bond the semiconductor element portion and the bonding surface of the support substrate with high positioning accuracy.

  In the method for manufacturing a semiconductor laser device according to the second aspect, preferably, prior to the step of cleaving both the semiconductor element portion and the support substrate, a step of forming cleavage introduction grooves in both the semiconductor element portion and the support substrate. Further prepare. If comprised in this way, a semiconductor element part and a support substrate can each be easily cleaved by the cleavage introduction groove | channel formed in each of a semiconductor element part and a support substrate.

  The method for manufacturing a semiconductor laser device according to the second aspect preferably further includes a step of removing the growth substrate from the semiconductor element portion prior to the step of cleaving both the semiconductor element portion and the support substrate. With this configuration, the growth substrate is removed from the semiconductor element portion without being cleaved, so that the removed growth substrate can be repeatedly used as a growth substrate for other semiconductor element portions.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 1 is a perspective view showing a nitride-based semiconductor laser device according to a first embodiment of the present invention. FIG. 2 is a side view showing the nitride-based semiconductor laser device according to the first embodiment shown in FIG. FIGS. 3 and 4 are views for explaining the configuration of the nitride-based semiconductor laser device according to the first embodiment shown in FIG. A nitride-based semiconductor laser device 100 according to a first embodiment of the present invention will be described with reference to FIGS. In the first embodiment, a case where the present invention is applied to a nitride semiconductor laser element which is an example of a semiconductor laser element will be described.

  In the first embodiment, as shown in FIGS. 1 and 2, a nitride semiconductor laser device 100 includes a support substrate 10 made of p-type GaAs having a thickness of about 100 μm and a semiconductor device layer 20 made of a nitride semiconductor. And a semiconductor element portion 30 formed with the. Further, the bonding surface 11 of the support substrate 10 to the semiconductor element portion 30 and the semiconductor element portion 30 are bonded via a conductive adhesive layer 40 (see FIG. 2) made of AuSn solder or the like. Specifically, as shown in FIG. 3, the support substrate 10 is interposed through a conductive adhesive layer 40 formed between a p-side electrode 28 described later and a p-side electrode 26 on the semiconductor element unit 30 side. Bonded to the semiconductor element portion 30. The conductive adhesive layer 40 is an example of the “adhesive layer” in the present invention.

  In the first embodiment, as shown in FIGS. 1 and 2, the support substrate 10 has a pair of cleavage surfaces 12 and 13 and is disposed on the light emission direction side (arrow X1 direction side). The angle α formed between the cleavage plane 12 made of the (110) plane and the bonding surface 11 with respect to the semiconductor element portion 30 is configured to be an obtuse angle of about 100 degrees. Specifically, as shown in FIG. 4, the support substrate 10 is formed such that the bonding surface 11 with respect to the semiconductor element portion 30 is turned off by about 10 degrees in the [110] direction from the crystal plane (001) plane. Accordingly, the support substrate 10 can be easily cleaved at the cleavage plane ((110) plane) inclined by about 80 degrees with respect to the bonding surface 11, so that the light emission direction side (arrow The support substrate 10 can be formed such that the angle α formed between the cleavage surface 12 arranged on the X1 direction side and the bonding surface 11 with respect to the semiconductor element portion 30 is an obtuse angle of about 100 degrees. Further, the support substrate 10 has conductivity, and as shown in FIG. 3, on the upper surface (on the surface on the arrow Z1 direction side) and on the lower surface (on the surface on the arrow Z2 direction side), as shown in FIG. The p-side electrode 28 and the p-side electrode 29 are formed.

  As shown in FIGS. 1 to 3, the semiconductor element layer 20 includes an n-type AlGaN cladding layer 21, a multiple quantum well (MQW) active layer 22, and a p-type AlGaN cladding layer 23. Specifically, a multiple quantum well (MQW) active layer 22 is formed on the lower surface of the n-type AlGaN cladding layer 21 (on the surface on the arrow Z2 direction side). Note that another semiconductor layer such as a light guide layer (not shown) or a carrier block layer (not shown) may be formed between the n-type AlGaN cladding layer 21 and the MQW active layer 22. The MQW active layer 22 may be formed with a single layer or a single quantum well structure.

  Further, on the lower surface of the MQW active layer 22 (on the surface in the direction of the arrow Z2), a flat portion and a convex portion formed so as to protrude downward (in the direction of the arrow Z2) from a substantially central portion of the flat portion. A p-type AlGaN cladding layer 23 is formed. Note that another semiconductor layer such as a light guide layer (not shown) or a carrier block layer (not shown) may be formed between the MQW active layer 22 and the p-type AlGaN cladding layer 23. In addition, the convex portion of the p-type AlGaN cladding layer 23 constitutes a ridge portion 24 extending in the resonator direction (arrow X1 and X2 directions) as an optical waveguide of the semiconductor element portion 30.

Further, as shown in FIG. 3, the current blocking layer 25 made of SiO ₂ is formed on the lower surface (on the surface in the arrow Z2 direction side) of the flat portion other than the convex portion of the p-type AlGaN cladding layer 23 of the semiconductor element layer 20. Is formed.

  A p-side electrode 26 is formed in a predetermined region on the lower surface of the ridge portion 24 of the semiconductor element layer 20 and the current blocking layer 25 (on the surface on the arrow Z2 direction side). A contact layer (not shown) or an ohmic electrode having a smaller band gap than that of the p-type AlGaN cladding layer 23 may be formed between the ridge portion 24 and the p-side electrode 26. An n-side electrode 27 is formed on the upper surface of the n-type AlGaN cladding layer 21 of the semiconductor element layer 20 (on the surface on the arrow Z1 direction side).

In addition, as shown in FIG. 2, the semiconductor element portion 30 has a light emission surface 30 a composed of a (−1100) plane at the end on the arrow X1 direction side, and light on the end on the arrow X2 direction side. A reflective surface 30b is formed. In the first embodiment, the light emitting surface 30a and the light reflecting surface 30b are distinguished by the magnitude relation of the intensity of the laser light emitted from each resonator surface. That is, the light emitting surface 30a side having a relatively high laser beam emission intensity is a light emitting surface, and the light reflecting surface 30b side having a relatively low laser beam emission intensity is a light reflecting surface. The light emitting surface 30a and the light reflecting surface 30b of the nitride-based semiconductor laser device 100 are made of a dielectric made of an aluminum nitride (AlN) film, an alumina (Al ₂ O ₃ ) film, or the like by end face coating in the manufacturing process. A multilayer film (not shown) is formed.

  Here, in the first embodiment, as shown in FIG. 2, the light emitting surface 30 a of the semiconductor element portion 30 is the semiconductor element portion 30 of the cleavage surface 12 on the light emitting direction side (arrow X <b> 1 direction side) of the support substrate 10. It is arranged on the light emitting direction side (arrow X1 direction side) by a predetermined distance D1 (about 18 μm) from the end portion 14 on the side (arrow Z1 direction side). The cleavage surface 12 of the support substrate 10 is inclined at a predetermined angle (about 10 degrees) with respect to the light emitting surface 30a. Thereby, even when the position of the cleavage plane 12 of the support substrate 10 is slightly shifted (about ± 15 μm), the end portion 14 on the semiconductor element portion 30 side of the cleavage plane 12 is more than the light emitting surface 30 a of the semiconductor element portion 30. It is also possible to suppress the protrusion to the light emitting direction side.

  5 to 13 are views for explaining a manufacturing process of the nitride-based semiconductor laser device according to the first embodiment shown in FIG. A manufacturing process for the nitride-based semiconductor laser device 100 according to the first embodiment is now described with reference to FIGS. 1 and 5 to 13.

  First, as shown in FIG. 5, an InGaN release layer having a predetermined thickness is formed on the upper surface of an n-type GaN substrate 50 having a main surface made of (0001) by metal organic chemical vapor deposition (MOCVD). 60 is laminated. Then, the n-type AlGaN cladding layer 21, the MQW active layer 22, and the p-type AlGaN cladding layer 23 are sequentially stacked on the InGaN release layer 60 so as to have a predetermined thickness, thereby forming the semiconductor element layer 20. The n-type GaN substrate 50 is an example of the “growth substrate” in the present invention.

  Then, after forming a resist pattern by lithography on the upper surface of the p-type AlGaN clad layer 23, dry etching or the like is performed using the resist pattern as a mask, so that the [1-100] direction (the arrow X2 direction in FIG. 1). Is formed.

A current blocking layer 25 made of SiO ₂ having a predetermined thickness is formed on the upper surface of the p-type AlGaN cladding layer 23 other than the ridge portion 24 and on both side surfaces of the ridge portion 24. Thereafter, a p-side electrode 26 having a predetermined thickness is formed in a predetermined region on the current blocking layer 25 by vacuum deposition so as to be in contact with the upper surface of the ridge portion 24. In this way, the structure of the semiconductor element portion 30 on the growth substrate side is formed.

  Thereafter, as shown in FIG. 6, in order to cleave the semiconductor element portion 30 at a desired position, in the vicinity of the ridge portion 24 at the boundary portion of each semiconductor element portion 30 in the [1-100] direction (arrow X2 direction). Cleavage introduction grooves 30c extending in the directions of arrows Y1 and Y2 are formed by etching or a scriber (for example, using a diamond point or laser light) in a region excluding.

  Next, as shown in FIG. 7, bonding of the support substrate 10 (p-type GaAs substrate) having a thickness of about 400 μm in which the bonding surface 11 to the semiconductor element portion 30 is turned off by about 10 degrees in the [110] direction from the (100) plane. On the surface 11, a p-side electrode 28 having a predetermined thickness and a conductive adhesive layer 40 made of AuSn solder or the like are formed by vacuum deposition. In this way, a structure on the support substrate side is formed.

  Next, as shown in FIG. 8, the p-side electrode 26 side of the semiconductor element portion 30 formed on the n-type GaN substrate 50 side shown in FIG. 5 and the p-side electrode 28 of the support substrate 10 shown in FIG. Join so that the sides face each other.

Thereafter, the second harmonic (wavelength: about 532 nm) of the Nd: YAG laser light is adjusted to an energy density of about 500 mJ / cm ² to about 1000 mJ / cm ² , and then the back side of the n-type GaN substrate 50 (see FIG. 8 toward the n-type GaN substrate 50. The laser light is irradiated over the entire area of the lower surface side (arrow Z2 direction side in FIG. 8) of the n-type GaN substrate 50. Then, the crystal bond of the InGaN release layer 60 laminated inside is entirely or locally broken by the laser light irradiation. As a result, the n-type GaN substrate 50 can be separated (peeled) from the semiconductor element portion 30 along the fracture region of the InGaN release layer 60. As long as the laser light has a wavelength that transmits GaN and is absorbed by the InGaN release layer 60, a laser light source other than the YAG laser light may be used. The separated n-type GaN substrate 50 can be reused by performing a surface treatment.

  Next, as shown in FIGS. 9 and 10, vacuum deposition is performed on the upper surface (on the surface in the direction of arrow Z1) of the semiconductor element layer 20 (n-type AlGaN cladding layer 21) from which the n-type GaN substrate 50 has been removed. An n-side electrode 27 having a predetermined thickness is formed by the method. Further, a p-side electrode 29 having a predetermined thickness is formed on the back surface of the support substrate 10 adjusted to a thickness of about 100 μm by polishing or etching (on the surface on the arrow Z2 direction side) by a vacuum deposition method. In this way, the nitride semiconductor laser device 100 in the wafer state is formed.

  Then, as shown in FIG. 11, in the vicinity of the edge of the wafer on the back surface of the support substrate 10 (on the surface on the arrow Z2 direction side), at a position corresponding to the cleavage introduction groove 30 c formed in the semiconductor element portion 30, Cleavage introduction groove 10a is formed to extend in the directions of arrows Y1 and Y2.

Thereafter, as shown in FIG. 12, the pressing member 70 is pressed against the wafer in a state where the cutting edge of the wedge-shaped pressing member 70 is aligned with the cleavage introduction groove 30c formed in the semiconductor element portion 30 in the wafer state. As a result, the support substrate 10 is cleaved at the (110) plane, and the bar-shaped nitride-based semiconductor laser device 100 is formed. Further, end face coating is performed on the bar-shaped nitride semiconductor laser element 100. Thus, a dielectric multilayer film made of an aluminum nitride (AlN) film, an alumina (Al ₂ O ₃ ) film, or the like is formed on the light emitting surface 30a and the light reflecting surface 30b (see FIG. 2) of the nitride-based semiconductor laser device 100. (Not shown) are formed.

  Further, as shown in FIG. 13, the bar-shaped nitride-based semiconductor laser device 100 shown in FIG. 12 is sequentially divided along the direction in which the resonator extends (the directions of arrows X1 and X2 in FIG. 10). Chip). Thus, the nitride semiconductor laser device 100 according to the first embodiment is manufactured.

  In the first embodiment, as described above, the angle α formed between the cleavage surface 12 of the support substrate 10 on the light emission direction side (arrow X1 direction side) and the bonding surface 11 of the support substrate 10 with respect to the semiconductor element portion 30 is about 100. By configuring the support substrate 10 to have an obtuse angle of degrees, as shown in FIG. 2, the cleavage surface 12 on the light emission direction side of the support substrate 10 and the bonding surface 11 of the support substrate 10 with respect to the semiconductor element portion 30 are formed. Compared to the case where the angle formed is a right angle, the portion of the cleavage surface 12 of the support substrate 10 on the semiconductor element portion 30 side can be further separated from the laser light having a predetermined radiation angle, so a part of the laser light Can be prevented from being blocked by the support substrate 10. Thereby, since it is not necessary to provide a cutting part etc. in the support substrate 10 so that a part of laser beam may not be blocked | interrupted, it can suppress that a manufacturing process increases. In addition, since it is not necessary to arrange the light emitting portion of the semiconductor element portion 30 in accordance with the cutting portion of the support substrate 10 or the like, it is not necessary to join the semiconductor element portion 30 and the support substrate 10 with high positioning accuracy.

  FIG. 14 is a side view showing a comparative example of the nitride-based semiconductor laser device according to the first embodiment shown in FIG. FIG. 15 is a graph showing far-field images of the nitride-based semiconductor laser device according to the first embodiment shown in FIG. 1 and a comparative example. Here, with reference to FIGS. 14 and 15, a nitride-based semiconductor laser device 110 as a comparative example will be described in comparison with the nitride-based semiconductor laser device 100 according to the first embodiment.

  As shown in FIG. 14, the support substrate 10 of the nitride-based semiconductor laser device 110 has a cleavage surface 12 on the light emission direction side (arrow X1 direction side) of the support substrate 10 and a bonding surface of the support substrate 10 with respect to the semiconductor element portion 30. 11 is formed so that an angle α formed with 11 is a right angle. For this reason, when the position of the cleavage surface 12 of the support substrate 10 is slightly shifted (about ± 15 μm), the end portion 14 on the semiconductor element portion 30 side of the cleavage surface 12 is lighter than the light emitting surface 30 a of the semiconductor element portion 30. It protrudes to the emission direction side. As a result, a part of the laser beam having a predetermined radiation angle is blocked by the support substrate 10, and as shown in FIG. 15, the light intensity of the laser beam irradiated on the support substrate 10 side (arrow Z2 direction side). Distribution becomes abnormal. On the other hand, in the nitride-based semiconductor laser device 100 according to the first embodiment of the present invention, it is possible to prevent a part of the laser light from being blocked by the support substrate 10, so that as shown in FIG. The graph of light intensity shows a single peak shape.

  In the first embodiment, the end portion 14 on the semiconductor element portion 30 side of the cleavage surface 12 on the light emission direction side (arrow X1 direction side) of the support substrate 10 is set to the light of the semiconductor element portion 30 with respect to the light emission direction. Since the cleavage surface 12 of the support substrate 10 can be further separated from the laser light by being arranged behind the emission surface 30a (in the direction of the arrow X2), a part of the laser light is blocked by the support substrate 10. It can be suppressed more.

(Second Embodiment)
FIG. 16 is a perspective view showing a nitride-based semiconductor laser device according to the second embodiment of the present invention. FIG. 17 is a front view showing the nitride-based semiconductor laser device according to the second embodiment shown in FIG. Referring to FIGS. 16 and 17, in the second embodiment, unlike the first embodiment, the ridge portion 224 of the semiconductor element portion 230 protrudes on the opposite side (arrow Z1 direction side) from the support substrate 10. The nitride based semiconductor laser device 200 thus formed will be described. In the second embodiment, a case where the present invention is applied to a nitride-based semiconductor laser element which is an example of a semiconductor laser element will be described.

  In the second embodiment, as shown in FIGS. 16 and 17, a nitride semiconductor laser element 200 includes a support substrate 10 made of p-type GaAs having a thickness of about 100 μm and a semiconductor element layer 220 made of a nitride semiconductor. And a semiconductor element portion 230 formed with the.

  As shown in FIG. 17, the semiconductor element layer 220 includes an n-type AlGaN cladding layer 221, a multiple quantum well (MQW) active layer 222, and a p-type AlGaN cladding layer 223. Specifically, on the lower surface (on the arrow Z2 direction side) of the n-type AlGaN cladding layer 221 having a flat portion and a convex portion formed so as to protrude upward (in the direction of arrow Z1) from the substantially central portion of the flat portion. A multiple quantum well (MQW) active layer 222 is formed on the surface). Further, a ridge portion 224 extending in the resonator direction (arrow X1 and X2 directions) is configured as an optical waveguide of the semiconductor element portion 230 by the convex portion of the n-type AlGaN cladding layer 221. A p-type AlGaN cladding layer 223 is formed on the lower surface of the MQW active layer 222 (on the surface on the arrow Z2 direction side).

Further, a current blocking layer 225 made of SiO ₂ is formed on the upper surface (on the surface on the arrow Z1 direction side) of the flat portion other than the convex portion of the n-type AlGaN cladding layer 221 of the semiconductor element layer 220.

  In addition, an n-side electrode 226 is formed in a predetermined region on the upper surface of the ridge portion 224 of the semiconductor element layer 220 and the current blocking layer 225 (on the surface on the arrow Z1 direction side). A p-side electrode 227 is formed on the lower surface of the p-type AlGaN cladding layer 223 of the semiconductor element layer 220 (on the surface on the arrow Z2 direction side).

  Further, as shown in FIG. 16, the semiconductor element portion 230 has a light emitting surface 230a formed at the end on the arrow X1 direction side and a light reflecting surface 230b formed on the end on the arrow X2 direction side. Yes.

  18 to 21 are views for explaining a manufacturing process of the nitride-based semiconductor laser device according to the second embodiment shown in FIG. A manufacturing process for the nitride-based semiconductor laser device 200 according to the second embodiment is now described with reference to FIGS.

  First, as shown in FIG. 18, an InGaN release layer having a predetermined thickness is formed on the upper surface of an n-type GaN substrate 250 having a main surface made of (0001) by metal organic chemical vapor deposition (MOCVD). 260 is laminated. Then, the n-type AlGaN cladding layer 221, the MQW active layer 222, and the p-type AlGaN cladding layer 223 are sequentially stacked on the InGaN release layer 260 so as to have a predetermined thickness, thereby forming the semiconductor element layer 220. The n-type GaN substrate 250 is an example of the “growth substrate” in the present invention.

  Then, a p-side electrode 227 having a predetermined thickness is formed in a predetermined region on the upper surface of the p-type AlGaN cladding layer 223 by vacuum deposition.

  Thereafter, as shown in FIG. 19, in order to cleave the semiconductor element portion 230 at a desired position, a ridge portion 224 is formed at a boundary portion of each semiconductor element portion 230 in the [1-100] direction (arrow X2 direction). A cleaved introduction groove 230c extending in the directions of arrows Y1 and Y2 is formed in a region that is not formed by etching or a scriber (for example, using a diamond point or a laser beam).

  Next, as shown in FIG. 20, the p-side electrode 227 side of the semiconductor element portion 230 formed on the n-type GaN substrate 250 side shown in FIG. 18 and the p-side electrode 28 of the support substrate 10 shown in FIG. Join so that the sides face each other.

Thereafter, the second harmonic (wavelength: about 532 nm) of the Nd: YAG laser light is adjusted to an energy density of about 500 mJ / cm ² to about 1000 mJ / cm ² , and then the back surface side of the n-type GaN substrate 250 (see FIG. 20 toward the n-type GaN substrate 250. The laser light is irradiated over the entire area of the lower surface side (arrow Z2 direction side in FIG. 20) of the n-type GaN substrate 250. Then, the crystal bond of the InGaN release layer 260 laminated inside is entirely or locally broken by the laser light irradiation. As a result, the n-type GaN substrate 250 can be separated (peeled) from the semiconductor element portion 230 along the fracture region of the InGaN release layer 260.

  Then, as shown in FIG. 21, after forming a resist pattern by lithography on the upper surface of the n-type AlGaN cladding layer 221, by performing dry etching or the like using the resist pattern as a mask, the [1-100] direction ( A ridge portion 224 extending in the direction of arrow X2 in FIG. 16 is formed.

Further, a current blocking layer 225 made of SiO ₂ having a predetermined thickness is formed on the upper surface of the n-type AlGaN cladding layer 221 other than the ridge portion 224 and on both side surfaces of the ridge portion 224. Thereafter, an n-side electrode 226 having a predetermined thickness is formed in a predetermined region on the current blocking layer 225 by vacuum deposition so as to be in contact with the upper surface of the ridge portion 224.

  Next, a p-side electrode 29 having a predetermined thickness is formed on the back surface of the support substrate 10 adjusted to a thickness of about 100 μm by polishing or etching (on the surface on the arrow Z2 direction side) by vacuum deposition. . In this manner, a nitride semiconductor laser element 200 in a wafer state is formed.

  The remaining structure of the second embodiment is the same as that of the first embodiment.

  In the second embodiment, as described above, the ridge portion 224 of the semiconductor element portion 230 is formed so as to protrude on the opposite side (arrow Z1 direction side) from the support substrate 10, thereby supporting the semiconductor element portion 230. Since the ridge portion 224 can be separated from the bonding surface with respect to the substrate 10, the load applied to the ridge portion 224 when the semiconductor element portion 230 and the support substrate 10 are bonded can be reduced.

  The remaining effects of the second embodiment are similar to those of the aforementioned first embodiment.

(Third embodiment)
FIG. 22 is a side view showing a nitride-based semiconductor laser device according to the third embodiment of the present invention. Referring to FIG. 22, in the third embodiment, unlike the first embodiment, bonding to the end surface 313 of the support substrate 310 on the side opposite to the light emission direction side (arrow X2 direction side) and the semiconductor element unit 30 is performed. The nitride semiconductor laser device 300 in which the angle β formed with the surface 311 is an obtuse angle will be described. In the third embodiment, a case where the present invention is applied to a nitride semiconductor laser element which is an example of a semiconductor laser element will be described.

  In the third embodiment, as shown in FIG. 22, a nitride-based semiconductor laser device 300 includes a support substrate 310 made of p-type GaAs having a thickness of about 100 μm and a semiconductor device layer 20 made of a nitride semiconductor. And a semiconductor element section 30.

  The support substrate 310 has a cleavage surface 312 on the light emission direction side (arrow X1 direction side), and an angle α formed by the cleavage surface 312 and the bonding surface 311 with respect to the semiconductor element portion 30 is an obtuse angle of about 100 degrees. It is configured. The support substrate 310 has an end surface 313 formed by etching or the like on the side opposite to the light emission direction side (arrow X2 direction side), and an angle β formed between the end surface 313 and the bonding surface 311 with respect to the semiconductor element portion 30. Is configured to have an obtuse angle of about 100 degrees.

  Further, the light emitting surface 30a of the semiconductor element portion 30 is outside the end portion 314 of the cleavage surface 312 on the light emitting direction side (arrow X1 direction side) of the support substrate 310 on the semiconductor element portion 30 side (arrow Z1 direction side). (Arrow X1 direction side). The light reflecting surface 30b of the semiconductor element portion 30 is an end portion 315 on the semiconductor element portion 30 side (arrow Z1 direction side) of the end surface 313 opposite to the light emitting direction side of the support substrate 310 (arrow X2 direction side). It arrange | positions outside (arrow X2 direction side).

  The remaining structure of the third embodiment is similar to that of the aforementioned first embodiment.

  In the third embodiment, as described above, by forming the support substrate 310 so that the angle β formed between the end surface 313 and the bonding surface 311 with respect to the semiconductor element portion 30 is an obtuse angle of about 100 degrees, the end surface 313 and the semiconductor are formed. Compared with the case where the angle β formed by the bonding surface 311 with respect to the element portion 30 is a right angle, the portion of the cleavage surface of the support substrate 310 on the semiconductor element portion 30 side is further separated from the laser light having a predetermined radiation angle. Therefore, a part of the laser light emitted from the light reflection surface 30b side can be prevented from being blocked by the support substrate 310.

  In the third embodiment, the light emitting surface 30a of the semiconductor element unit 30 is arranged on the side of the semiconductor element 30 (arrow Z1 direction side) of the cleavage surface 312 on the light emitting direction side (arrow X1 direction side) of the support substrate 310. The light reflection surface 30b of the semiconductor element portion 30 is disposed outside the end portion 314 (arrow X1 direction side), and the end surface 313 on the opposite side (arrow X2 direction side) of the support substrate 310 from the light emission direction side. Since the light emitting surface 30a and the light reflecting surface 30b are more exposed by disposing them on the outer side (arrow X2 direction side) than the end portion 315 on the semiconductor element portion 30 side (arrow Z1 direction side), The end face coating process can be performed on the emission surface 30a and the light reflection surface 30b.

  The remaining effects of the third embodiment are similar to those of the aforementioned first embodiment.

(Fourth embodiment)
FIG. 23 is a side view showing a nitride-based semiconductor laser device according to the fourth embodiment of the present invention. Referring to FIG. 23, in the fourth embodiment, unlike the first embodiment, a nitride in which a part of the end surface 412 on the light emission direction side (arrow X1 direction side) of the support substrate 410 is a cleavage surface 412a. The semiconductor laser device 400 will be described. In the fourth embodiment, a case where the present invention is applied to a nitride semiconductor laser element which is an example of a semiconductor laser element will be described.

  In the fourth embodiment, as shown in FIG. 23, a nitride-based semiconductor laser device 400 includes a support substrate 410 made of p-type GaAs having a thickness of about 100 μm and a semiconductor device layer 20 made of a nitride semiconductor. And a semiconductor element section 30.

  The support substrate 410 has an end face 412 on the light emission direction side (arrow X1 direction side), and a part of the end face 412 on the semiconductor element part 30 side is a cleavage plane 412a. Further, the support substrate 410 is configured such that an angle α formed by the cleavage surface 412a and the bonding surface 411 with respect to the semiconductor element portion 30 is an obtuse angle of about 100 degrees.

  The remaining structure of the fourth embodiment is similar to that of the aforementioned first embodiment.

  In the fourth embodiment, as described above, the cleavage surface 412a is provided on a part of the end surface 412 on the light emission direction side (arrow X1 direction side) of the support substrate 410, and the support substrate 410 is separated from the cleavage surface 412a and the semiconductor element portion. By configuring the support substrate 410 so that the angle α formed by the bonding surface 411 with respect to 30 becomes an obtuse angle of about 100 degrees, the angle α formed by the cleavage surface 412a and the bonding surface 411 with respect to the semiconductor element unit 30 is a right angle. Compared to the case, the portion of the cleavage surface 412a of the support substrate 410 on the semiconductor element portion 30 side can be further separated from the laser light having a predetermined radiation angle, so that part of the laser light is blocked by the support substrate 410. Can be suppressed.

  The remaining effects of the fourth embodiment are similar to those of the aforementioned first embodiment.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims for patent, and further includes all modifications within the meaning and scope equivalent to the scope of claims for patent.

  For example, in the first to fourth embodiments, the example using the support substrate made of GaAs has been described. However, the present invention is not limited to this, and the cleavage properties such as Ge, Si, and InP are good. A support substrate made of another material may be used.

  In the first to fourth embodiments, the example in which the support substrate is formed so that the bonding surface with respect to the semiconductor element portion is turned off by about 10 degrees in the [110] direction from the (001) plane has been shown. The present invention is not limited to this, so that the bonding surface with respect to the semiconductor element portion is turned off by an angle other than about 10 degrees (preferably about 2 degrees to about 20 degrees) in the [110] direction from the (001) plane. A support substrate may be formed. In this case, the angle formed between the cleavage plane disposed on the light emitting direction side and the bonding surface with respect to the semiconductor element portion may be other than about 100 degrees (preferably, about 92 degrees to about 110 degrees). . The bonding surface may be a crystal plane other than the (001) plane, and the tilt direction may be other than [110].

  In the first to fourth embodiments, AuSn solder is used as the conductive adhesive layer. However, the present invention is not limited to this, and other materials such as Au, Sn, In, Pb, and Ge, and A conductive adhesive layer made of an alloy material may be used.

In the first to fourth embodiments, the dielectric multilayer film formed on the resonator surface (light emitting surface and light reflecting surface) of the nitride-based semiconductor element is made of aluminum nitride containing aluminum (Al) element. Although an example in which a film, an alumina (Al ₂ O ₃ ) film, or the like is applied is shown, the present invention is not limited to this, and for example, SiO ₂ , ZrO ₂ , Ta ₂ O ₅ , Nb ₂ O ₅ , La ₂ O ₃ Alternatively, a single layer or a multilayer film made of SiN, GaN, BN, or Ti ₃ O ₅ or Nb ₂ O ₃ which are materials having different composition ratios may be used.

  In the first to fourth embodiments, the example in which the p-type cladding layer (p-type AlGaN cladding layer) is disposed on the support substrate (p-type GaAs substrate) side is shown. However, the n-type cladding layer may be disposed on the support substrate side. In this case, an n-type GaAs substrate is used as the support substrate.

  In the nitride semiconductor laser device manufacturing process according to the first embodiment and the second embodiment, an n-type cladding layer (n-type AlGaN cladding layer) is sequentially formed on an n-type GaN substrate as a growth substrate. However, the present invention is not limited to this, and a p-type cladding layer may be formed in order on the growth substrate. In this case, an n-type GaAs substrate is used as the support substrate.

  In the third embodiment, an example is shown in which the side surface of the support substrate opposite to the light emission direction side is formed by etching or the like. However, the present invention is not limited to this and may be formed by cleaving. Good.

  Moreover, in the said 1st Embodiment-4th Embodiment, in the manufacturing process of the semiconductor laser element, although the GaN substrate which has the main surface which consists of (0001) plane was used as a growth substrate, this invention is not limited to this, A GaN substrate whose main surface is the (1-100) plane or the (11-20) plane may be used as the growth substrate. When these substrates are used, the emission surface of the semiconductor laser element is (11-20), (-1-120), (0001), (000-1) plane in the former, and (1-100) in the latter. , (−1100), (0001), (000-1) planes and the like are preferable. Furthermore, a GaN substrate having a main surface with a plane inclined from several degrees to several tens of degrees in the [1-100] or [11-20] direction from the (0001) or (000-1) plane may be used. Depending on the structure, the effect of the internal electric field can be reduced compared to the case of using a GaN substrate having the (0001) plane as the main surface, and the light emission characteristics of the semiconductor laser device can be further improved.

  Moreover, in the said 1st Embodiment-4th Embodiment, although GaN was illustrated as a material of a growth substrate, you may use the nitride semiconductor which consists of AlN, InN, or those mixed crystals, and C surface nitriding A C-plane sapphire substrate on which a semiconductor is grown, an R-plane sapphire substrate on which an A-plane nitride semiconductor is grown, an A-plane or M-plane SiC substrate on which an A-plane or M-plane nitride semiconductor is grown can be substituted. The same applies to a LiAlO2-LiGaO2 substrate having an A-plane or M-plane nitride semiconductor.

1 is a perspective view showing a nitride-based semiconductor laser device according to a first embodiment of the present invention. FIG. 2 is a side view showing the nitride-based semiconductor laser device according to the first embodiment shown in FIG. 1. FIG. 2 is a front view showing the nitride-based semiconductor laser device according to the first embodiment shown in FIG. 1. FIG. 2 is a view for explaining the configuration of the nitride-based semiconductor laser device according to the first embodiment shown in FIG. 1. FIG. 8 is a diagram for explaining a manufacturing process for the nitride-based semiconductor laser device according to the first embodiment shown in FIG. 1. FIG. 8 is a diagram for explaining a manufacturing process for the nitride-based semiconductor laser device according to the first embodiment shown in FIG. 1. FIG. 8 is a diagram for explaining a manufacturing process for the nitride-based semiconductor laser device according to the first embodiment shown in FIG. 1. FIG. 8 is a diagram for explaining a manufacturing process for the nitride-based semiconductor laser device according to the first embodiment shown in FIG. 1. FIG. 8 is a diagram for explaining a manufacturing process for the nitride-based semiconductor laser device according to the first embodiment shown in FIG. 1. FIG. 8 is a diagram for explaining a manufacturing process for the nitride-based semiconductor laser device according to the first embodiment shown in FIG. 1. FIG. 8 is a diagram for explaining a manufacturing process for the nitride-based semiconductor laser device according to the first embodiment shown in FIG. 1. FIG. 8 is a diagram for explaining a manufacturing process for the nitride-based semiconductor laser device according to the first embodiment shown in FIG. 1. FIG. 8 is a diagram for explaining a manufacturing process for the nitride-based semiconductor laser device according to the first embodiment shown in FIG. 1. FIG. 3 is a side view showing a comparative example of the nitride-based semiconductor laser device according to the first embodiment shown in FIG. 1. 2 is a graph showing far-field images of the nitride-based semiconductor laser device according to the first embodiment shown in FIG. 1 and a comparative example. It is the perspective view which showed the nitride type semiconductor laser element by 2nd Embodiment of this invention. FIG. 17 is a front view showing the nitride-based semiconductor laser device according to the second embodiment shown in FIG. 16. FIG. 17 is a diagram for explaining a manufacturing process for the nitride-based semiconductor laser device according to the second embodiment shown in FIG. 16. FIG. 17 is a diagram for explaining a manufacturing process for the nitride-based semiconductor laser device according to the second embodiment shown in FIG. 16. FIG. 17 is a diagram for explaining a manufacturing process for the nitride-based semiconductor laser device according to the second embodiment shown in FIG. 16. FIG. 17 is a diagram for explaining a manufacturing process for the nitride-based semiconductor laser device according to the second embodiment shown in FIG. 16. It is the side view which showed the nitride-type semiconductor laser element by 3rd Embodiment of this invention. It is the side view which showed the nitride-type semiconductor laser element by 4th Embodiment of this invention.

Explanation of symbols

10, 310, 410 Support substrate 11, 311, 411 Bonding surface 12, 312, 412a Cleaved surface 14, 314 End portion 30, 230 Semiconductor element portion 30a, 230a Light emitting surface 40 Conductive adhesive layer (adhesive layer)
50, 250 n-type GaN substrate (growth substrate)
100, 200, 300, 400 Nitride semiconductor laser element (semiconductor laser element)

Claims (9)

A support substrate having a cleavage plane;
A semiconductor element portion bonded to the support substrate,
A semiconductor laser element, wherein an angle formed between a cleavage plane of the support substrate on a light emitting direction side and a bonding surface of the support substrate with respect to the semiconductor element portion is an obtuse angle.   2. The semiconductor laser device according to claim 1, wherein a bonding surface of the support substrate to the semiconductor element portion is inclined at a predetermined angle from a crystal plane of the support substrate.   The end of the cleaved surface of the support substrate on the light emission direction side on the semiconductor element portion side is disposed behind the light emission surface of the semiconductor element portion with respect to the light emission direction. Or the semiconductor laser element of 2.   The semiconductor laser device according to claim 1, wherein the support substrate and the semiconductor element portion are bonded via an adhesive layer.   The semiconductor laser device according to claim 1, wherein the semiconductor element portion is made of a nitride-based semiconductor.   The semiconductor laser device according to claim 1, wherein the support substrate has conductivity. A step of growing a semiconductor element portion on a growth substrate;
Bonding the bonding surface of the support substrate having a bonding surface inclined at a predetermined angle from the crystal plane, and the semiconductor element portion;
Cleaving both the semiconductor element portion and the support substrate so that the angle formed between the cleavage surface of the support substrate on the light emitting direction side and the bonding surface of the support substrate with respect to the semiconductor element portion is an obtuse angle; A method for manufacturing a semiconductor laser device.   The semiconductor laser device according to claim 7, further comprising a step of forming a cleavage introduction groove in both the semiconductor element portion and the support substrate prior to the step of cleaving both the semiconductor element portion and the support substrate. Production method.   9. The method of manufacturing a semiconductor laser device according to claim 7, further comprising a step of removing the growth substrate from the semiconductor element portion prior to the step of cleaving both the semiconductor element portion and the support substrate.

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