JP4056481B2 - Semiconductor device and manufacturing method thereof - Google Patents

Description

  The present invention relates to a semiconductor element and a manufacturing method thereof, and more particularly to a semiconductor element having a semiconductor element layer formed on a substrate and a manufacturing method thereof.

  Conventionally, a light-emitting diode element, a semiconductor laser element, and the like are known as a semiconductor element in which a semiconductor element layer is formed on a substrate (see, for example, Patent Document 1).

  Patent Document 1 discloses a nitride semiconductor laser element in which a plurality of nitride semiconductor layers are formed on a nitride semiconductor substrate. Specifically, in the nitride-based semiconductor laser device disclosed in Patent Document 1, an n-type nitride-based semiconductor layer, a light-emitting layer made of a nitride-based semiconductor, and p-type nitridation are formed on an n-type GaN substrate. Physical semiconductor layers are sequentially formed. In the p-type nitride semiconductor layer, a ridge portion as a current passage portion is formed, and a p-side electrode is formed on the ridge portion. An n-side electrode is formed on the back surface of the n-type GaN substrate.

In the semiconductor element in which the electrode is formed on the back surface of the substrate as described above, when dislocations exist on the back surface of the substrate, a leak current is generated by current flowing in a region where dislocations exist on the back surface of the substrate. For this reason, in Patent Document 1, dislocations existing in the n-type GaN substrate are reduced by producing the n-type GaN substrate by lateral growth. As a specific method for manufacturing a substrate, first, a mask layer is formed on a predetermined portion on the sapphire substrate, and then the n-type GaN layer is laterally grown on the sapphire substrate using the mask layer as a selective growth mask. At this time, the n-type GaN layer selectively grows in the vertical direction on the portion of the sapphire substrate where the mask layer is not formed, and then gradually grows in the horizontal direction. Thus, since the dislocations are bent in the lateral direction as the n-type GaN layer grows in the lateral direction, propagation of the dislocations in the vertical direction is suppressed. As a result, an n-type GaN layer with reduced dislocation reaching the upper surface is formed. Thereafter, a region (such as a sapphire substrate) including a mask layer located under the n-type GaN layer is removed, thereby forming an n-type GaN substrate with reduced dislocations.
JP-A-11-214798

  However, the method of Patent Document 1 has a disadvantage in that a region where dislocations are concentrated is formed on a region where a mask layer in which growth proceeds in the vertical direction is not formed. When an n-type GaN substrate is fabricated from an n-type GaN layer having such dislocation-concentrated regions, an n-side electrode is formed in a region where dislocations are concentrated on the back surface of the n-type GaN substrate. There is an inconvenience that a leak current is generated when a current flows in a region where dislocations are concentrated on the back surface of the n-type GaN substrate. In this case, since the light output when the element is driven at a constant current becomes unstable, there is a problem that it is difficult to stabilize the operation of the element.

  The present invention has been made to solve the above-described problems, and one object of the present invention is to provide a semiconductor device capable of stabilizing the operation of the device.

  Another object of the present invention is to provide a method of manufacturing a semiconductor device capable of stabilizing the operation of the device.

Means for Solving the Problems and Effects of the Invention

  A semiconductor element according to one aspect of the present invention is formed on a surface of a substrate and has a semiconductor element layer having a surface region where dislocations are concentrated on at least a part of the surface, and a surface region where dislocations are concentrated A concave portion formed in the inner region and a surface-side electrode formed so as to be in contact with a region on the surface of the semiconductor element layer other than the surface region where dislocations are concentrated are provided.

  In the semiconductor element according to this one aspect, as described above, a recess is formed in a region inside the region where dislocations are concentrated on the surface of the semiconductor element layer, and dislocations are concentrated on the surface of the semiconductor element layer. By forming the surface-side electrode so as to be in contact with a region other than the region where the current is present, the generation of leakage current due to current flowing through the region where dislocations are concentrated on the surface of the semiconductor element layer is suppressed. Can do. As a result, the light output during constant current driving of the element can be stabilized, so that the operation of the semiconductor element can be stabilized. In addition, when applied to a light-emitting element as an example of a semiconductor element, a region inside the region where dislocations are concentrated on the surface of the semiconductor element layer and a region where dislocations are concentrated on the surface of the semiconductor element layer are recessed. Therefore, light generated in the region inside the surface where the dislocations are concentrated on the surface of the semiconductor element layer is prevented from being absorbed in the region where the dislocations are concentrated on the surface of the semiconductor element layer. can do. As a result, it is possible to suppress the light absorbed in the region where dislocations are concentrated from being emitted again at an unintended wavelength, and thus it is possible to suppress the deterioration in color purity caused by such re-emission. .

  In the semiconductor element, preferably, the substrate has a back surface region where dislocations are concentrated on at least a part of the back surface, and is in contact with a region on the back surface of the substrate other than the back surface region where dislocations are concentrated. The back surface side electrode formed in is further provided. With this configuration, it is possible to suppress the occurrence of a leak current due to the current flowing in the region where dislocations are concentrated on the back surface of the substrate. As a result, the optical output during constant current driving of the element can be stabilized, so that the operation of the semiconductor element can be stabilized even when there is a region where dislocations are concentrated on the back surface of the substrate. it can. In addition, since current flowing in a region where dislocations are concentrated can be reduced, unnecessary light emission from the region where dislocations are concentrated can be reduced.

  In this case, it is preferable to further include an insulating film formed on the back surface region where dislocations are concentrated. With this configuration, since the region where dislocations are concentrated on the back surface of the substrate is covered with the insulating film so as not to be exposed, current easily flows to the region where dislocations are concentrated on the back surface of the substrate. It is possible to suppress the occurrence of leak current due to the above.

  In the semiconductor element, the substrate may include a nitride semiconductor substrate. If comprised in this way, it can suppress that a leak current generate | occur | produces in the nitride-type semiconductor substrate.

  In the semiconductor element, the side surface of the back surface side electrode may be provided at a position spaced a predetermined distance inward from the side surface of the substrate. If comprised in this way, when fusing solder to a back surface side electrode, it can suppress that a solder flows to the side end surface of the semiconductor element layer formed on the board | substrate, for example. Thereby, generation | occurrence | production of the short circuit defect of a semiconductor element can be suppressed.

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

(First reference form)
FIG. 1 is a cross-sectional view showing the structure of a nitride-based semiconductor laser device (semiconductor device) according to the first embodiment of the present invention. FIG. 2 is an enlarged cross-sectional view showing details of the light emitting layer of the nitride-based semiconductor laser device according to the first embodiment shown in FIG. First, the structure of the nitride-based semiconductor laser device according to the first embodiment will be described with reference to FIGS.

In the nitride-based semiconductor laser device according to the first embodiment, as shown in FIG. 1, a wurtzite structure having a thickness of about 100 μm and doped with oxygen having a carrier concentration of about 5 × 10 ¹⁸ cm ^−3. An n-type layer 2 made of n-type GaN doped with Si having a thickness of about 100 nm and a doping amount of about 5 × 10 ¹⁸ cm ⁻³ is formed on the (0001) plane of the n-type GaN substrate 1. Is formed. on the n-type layer 2 has a thickness of about 400 nm, n-type Si doped with a carrier concentration of about 5 × ¹⁰ 18 ^{cm -3} doping amount and about 5 × ¹⁰ 18 ^{cm -3} Al _{0 An} n-type clad layer 3 made of _.05 Ga _0.95 N is formed. The n-type GaN substrate 1 is an example of the “substrate” and “nitride-based semiconductor substrate” in the present invention, and the n-type layer 2 and the n-type cladding layer 3 are examples of the “semiconductor element layer” in the present invention. It is.

A light emitting layer 4 is formed on the n-type cladding layer 3. As shown in FIG. 2, the light emitting layer 4 includes an n-type carrier block layer 4a, an n-type light guide layer 4b, a multiple quantum well (MQW) active layer 4e, a p-type light guide layer 4f, and a p-type. It is comprised from the cap layer 4g. n-type carrier block layer 4a has a thickness of about 5 nm, n-type Al ₀ doped with Si having a carrier concentration of about 5 × ¹⁰ 18 ^{cm -3} doping amount and about 5 × ¹⁰ 18 ^{cm -3} _0.1 Ga _0.9 N. n-type optical guide layer 4b, having a thickness of about 100 nm, from n-type GaN doped with Si having a carrier concentration of about 5 × ¹⁰ 18 ^{cm -3} doping amount and about 5 × ¹⁰ 18 ^{cm -3} Become. The MQW active layer 4e includes four barrier layers 4c made of undoped In _0.05 Ga _0.95 N having a thickness of about 20 nm and undoped In _0.15 Ga _0.85 N having a thickness of about 3 nm. The three well layers 4d made of are stacked alternately. The p-type light guide layer 4f has a thickness of about 100 nm and is doped with Mg having a doping amount of about 4 × 10 ¹⁹ cm ⁻³ and a carrier concentration of about 5 × 10 ¹⁷ cm ^−3. Made of GaN. The p-type cap layer 4g has a thickness of about 20 nm and is doped with Mg having a doping amount of about 4 × 10 ¹⁹ cm ⁻³ and a carrier concentration of about 5 × 10 ¹⁷ cm ⁻³ _{. It} consists of ₁ Ga _0.9 N. The light emitting layer 4 is an example of the “semiconductor element layer” in the present invention.

As shown in FIG. 1, the light emitting layer 4 has a convex portion and is doped with Mg having a doping amount of about 4 × 10 ¹⁹ cm ⁻³ and a carrier concentration of about 5 × 10 ¹⁷ cm ^−3. A p-type cladding layer 5 made of p-type Al _0.05 Ga _0.95 N is formed. The convex portion of the p-type cladding layer 5 has a width of about 1.5 μm and a height of about 300 nm. Further, the flat portion other than the convex portion of the p-type cladding layer 5 has a thickness of about 100 nm. On the convex portion of the p-type cladding layer 5, Mg having a thickness of about 10 nm and a doping amount of about 4 × 10 ¹⁹ cm ⁻³ and a carrier concentration of about 5 × 10 ¹⁷ cm ⁻³ is doped. A p-type contact layer 6 made of the p-type GaN is formed. The convex portion of the p-type cladding layer 5 and the p-type contact layer 6 constitute a striped (elongated) ridge portion 7 extending in a predetermined direction. The p-type cladding layer 5 and the p-type contact layer 6 are examples of the “semiconductor element layer” in the present invention.

  On the p-type contact layer 6 constituting the ridge portion 7, from the lower layer to the upper layer, there is a Pt layer having a thickness of about 5 nm, a Pd layer having a thickness of about 100 nm, and a thickness of about 150 nm. A p-side ohmic electrode 9 made of an Au layer is formed. The p-side ohmic electrode 9 is an example of the “surface-side electrode” in the present invention. An insulating film 10 made of a SiN film having a thickness of about 250 nm is formed on the surface of the flat portion other than the convex portion of the p-type cladding layer 5 so as to cover the side surfaces of the ridge portion 7 and the p-side ohmic electrode 9. Is formed. On the surface of the insulating film 10, a Ti layer having a thickness of about 100 nm, a Pd layer having a thickness of about 100 nm, and a Pd layer having a thickness of about 100 nm from the lower layer to the upper layer so as to be in contact with the upper surface of the p-side ohmic electrode 9. A p-side pad electrode 11 made of an Au layer having a thickness of 3 μm is formed.

Here, in the vicinity of the end portions of the n-type GaN substrate 1 and the nitride-based semiconductor layers (2 to 5), the surface extends from the back surface of the n-type GaN substrate 1 to the surface of the flat portion of the p-type cladding layer 5, and about Dislocation-concentrated regions 8 having a width of 10 μm are formed in stripes (elongated) with a period of about 400 μm. In the first reference embodiment, the insulating film 12 made of a SiO ₂ film having a thickness of about 250 nm and a width of about 40 μm so as to cover the region 8 where dislocations are concentrated on the back surface of the n-type GaN substrate 1. Is formed. On the back surface of the n-type GaN substrate 1, an n-side electrode 13 is in contact with a region other than the region 8 where dislocations are concentrated on the back surface of the n-type GaN substrate 1 and covers the insulating film 12. Is formed. The n-side electrode 13 includes an Al layer having a thickness of about 10 nm, a Pt layer having a thickness of about 20 nm, and an Au layer having a thickness of about 300 nm in order from the side closer to the back surface of the n-type GaN substrate 1. Become. The n-side electrode 13 is an example of the “back side electrode” in the present invention.

  In the first reference embodiment, as described above, the insulating film 12 is formed in the region 8 where dislocations are concentrated on the back surface of the n-type GaN substrate 1 and the dislocations on the back surface of the n-type GaN substrate 1 are concentrated. By forming the n-side electrode 13 so as to be in contact with a region other than the region 8, the region 8 where dislocations on the back surface of the n-type GaN substrate 1 are concentrated is covered by the insulating film 12. Therefore, it is possible to easily suppress the occurrence of leakage current due to the current flowing through the region 8 where dislocations are concentrated on the back surface of the n-type GaN substrate 1. As a result, since the optical output during constant current driving of the element can be easily stabilized, the operation of the semiconductor element can be easily stabilized. In addition, since the current flowing through the region 8 where dislocations are concentrated can be reduced, unnecessary light emission from the region 8 where dislocations are concentrated can be reduced.

  3 to 12 are cross-sectional 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 according to the first embodiment will now be described with reference to FIGS.

First, the formation process of the n-type GaN substrate 1 will be described with reference to FIGS. Specifically, as shown in FIG. 3, using a MOCVD (Metal Organic Chemical Vapor Deposition) method, the substrate temperature is maintained on the sapphire substrate 21 at about 600 ° C. An AlGaN layer 22 having a thickness of 20 nm is grown. Thereafter, the substrate temperature is changed to about 1100 ° C., and a GaN layer 23 having a thickness of about 1 μm is grown on the AlGaN layer 22. At this time, dislocations propagated in the vertical direction are formed in the entire region of the GaN layer 23 at a density of about 5 × 10 ⁸ cm ⁻² or more (for example, about 5 × 10 ⁹ cm ⁻² ).

Next, as shown in FIG. 4, a mask made of SiN or SiO ₂ having a width of about 390 μm and a thickness of about 200 nm is formed on the GaN layer 23 with a gap of about 10 μm using the plasma CVD method. The layer 24 is formed in a stripe shape (elongated shape) with a period of about 400 μm.

Next, as shown in FIG. 5, using the HVPE (Halide Vapor Phase Epitaxy) method, the GaN layer is formed using the mask layer 24 as a selective growth mask with the substrate temperature maintained at about 1100 ° C. An oxygen-doped n-type GaN layer 1a having a thickness of about 150 μm and having a carrier concentration of about 5 × 10 ¹⁸ cm ⁻³ is laterally grown on the substrate 23. At this time, the n-type GaN layer 1a selectively grows in the vertical direction on the GaN layer 23 where the mask layer 24 is not formed, and then gradually grows in the horizontal direction. Therefore, the n-type GaN layer 1a located on the GaN layer 23 where the mask layer 24 is not formed has a density of about 5 × 10 ⁸ cm ⁻² or more (for example, about 5 × 10 ⁹ cm ⁻² ). The region 8 where dislocations propagated in the vertical direction are concentrated is formed in a stripe shape (elongated shape) with a width of about 10 μm. On the other hand, in the n-type GaN layer 1a located on the mask layer 24, dislocations are bent in the lateral direction as the n-type GaN layer 1a grows in the lateral direction, so that dislocations propagated in the vertical direction are formed. The dislocation density is less than about 5 × 10 ⁷ cm ⁻² (for example, about 1 × 10 ⁶ cm ⁻² ). Thereafter, a region (such as the sapphire substrate 21) including the mask layer 24 located under the n-type GaN layer 1a is removed. In this way, as shown in FIG. 6, an n-type GaN substrate 1 doped with oxygen having a carrier concentration of about 5 × 10 ¹⁸ cm ⁻³ is formed.

  Next, as shown in FIG. 7, the n-type layer 2, the n-type clad layer 3, the light emitting layer 4, the p-type clad layer 5, and the p-type contact layer 6 are formed on the n-type GaN substrate 1 using MOCVD. Grow sequentially.

Specifically, a carrier gas composed of H ₂ and N ₂ , a source gas composed of NH ₃ and TMGa, and a dopant gas composed of SiH ₄ are used with the substrate temperature maintained at a growth temperature of about 1100 ° C. Then, an n-type layer 2 made of n-type GaN doped with Si and having a thickness of about 100 nm and a doping amount of about 5 × 10 ¹⁸ cm ⁻³ is grown on the n-type GaN substrate 1. Thereafter, further addition of TMAl as a source gas, on the n-type layer 2, having a thickness of about 400 nm, carrier concentration of about 5 × ¹⁰ 18 ^{cm -3} doping amount and about 5 × ¹⁰ 18 ^{cm -3} An n-type clad layer 3 made of n-type Al _0.05 Ga _0.95 N doped with Si is grown.

Subsequently, as shown in FIG. 2, on the n-type cladding layer 3 (see FIG. 7), having a thickness of about 5 nm, the doping amount of about 5 × ¹⁰ 18 ^{cm -3} and about 5 × ¹⁰ 18 cm An n-type carrier block layer 4a made of n-type Al _0.1 Ga _0.9 N doped with Si having a carrier concentration of ⁻³ is grown.

Next, with the substrate temperature maintained at a growth temperature of about 800 ° C., using a carrier gas composed of H ₂ and N ₂ , a source gas composed of NH ₃ and TMGa, and a dopant gas composed of SiH ₄ , on the n-type carrier blocking layer 4a, about 5 × ¹⁰ 18 ^{cm -3} doping amount and about 5 × ¹⁰ 18 ^cm Si having a carrier concentration of ^-3 is doped n-type GaN n-type optical guide layer 4b Grow.

Thereafter, TMIn is further added to the source gas, and a barrier of four layers made of undoped In _0.05 Ga _0.95 N having a thickness of about 20 nm is formed on the n-type light guide layer 4b without using a dopant gas. The MQW active layer 4e is formed by alternately growing the layer 4c and the three well layers 4d made of undoped In _0.15 Ga _0.85 N having a thickness of about 3 nm.

Then, the changing material gas NH ₃ and TMGa, using a dopant gas of _Cp 2 Mg, on the MQW active layer 4e, having a thickness of about 100 nm, the doping amount of about 4 × ¹⁰ 19 ^{cm -3} Then, a p-type light guide layer 4f made of p-type GaN doped with Mg having a carrier concentration of about 5 × 10 ¹⁷ cm ⁻³ is grown. Thereafter, TMAl is further added to the source gas to have a thickness of about 20 nm on the p-type light guide layer 4f, a doping amount of about 4 × 10 ¹⁹ cm ⁻³ and about 5 × 10 ¹⁷ cm ⁻³ . A p-type cap layer 4g made of p-type Al _0.1 Ga _0.9 N doped with Mg having a carrier concentration is grown. Thereby, the light emitting layer 4 including the n-type carrier block layer 4a, the n-type light guide layer 4b, the MQW active layer 4e, the p-type light guide layer 4f, and the p-type cap layer 4g is formed.

Next, as shown in FIG. 7, with the substrate temperature maintained at a growth temperature of about 1100 ° C., a carrier gas composed of H ₂ and N ₂ , a source gas composed of NH ₃ , TMGa and TMAl, and Cp ₂ Mg having a thickness of about 400 nm, a doping amount of about 4 × 10 ¹⁹ cm ⁻³ and a carrier concentration of about 5 × 10 ¹⁷ cm ⁻³ on the light emitting layer 4 using a dopant gas made of Mg. A p-type cladding layer 5 made of p-type Al _0.05 Ga _0.95 N doped with is grown. Thereafter, the source gas is changed to NH ₃ and TMGa, and the p-type cladding layer 5 has a thickness of about 10 nm and a doping amount of about 4 × 10 ¹⁹ cm ⁻³ and about 5 × 10 ¹⁷ cm ^−3. A p-type contact layer 6 made of p-type GaN doped with Mg having a carrier concentration of 1 is grown.

  At this time, dislocations of the n-type GaN substrate 1 propagate to form a region 8 where dislocations are concentrated extending from the back surface of the n-type GaN substrate 1 to the upper surface of the p-type contact layer 6.

  Thereafter, annealing is performed under a temperature condition of about 800 ° C. in a nitrogen gas atmosphere.

  Next, as shown in FIG. 8, using a vacuum deposition method, a Pt layer having a thickness of about 5 nm and a thickness of about 100 nm are formed in a predetermined region on the p-type contact layer 6 from the lower layer to the upper layer. After forming the p-side ohmic electrode 9 composed of the Pd layer and the Au layer having a thickness of about 150 nm, the Ni layer 25 having a thickness of about 250 nm is formed on the p-side ohmic electrode 9. At this time, the p-side ohmic electrode 9 and the Ni layer 25 are formed in a stripe shape (elongated shape) having a width of about 1.5 μm.

Next, as shown in FIG. 9, a thickness of about 300 nm is etched from the upper surfaces of the p-type contact layer 6 and the p-type cladding layer 5 using the Ni layer 25 as a mask using dry etching with a Cl ₂ gas. . As a result, a striped (elongated) ridge portion 7 is formed which is composed of the convex portion of the p-type cladding layer 5 and the p-type contact layer 6 and extends in a predetermined direction. Thereafter, the Ni layer 25 is removed.

  Next, as shown in FIG. 10, a SiN film (not shown) having a thickness of about 250 nm is formed by plasma CVD so as to cover the entire surface, and then is formed on the upper surface of the p-side ohmic electrode 9. By removing the positioned SiN film, the insulating film 10 made of a SiN film having a thickness of about 250 nm is formed.

  Next, as shown in FIG. 11, a thickness of about 100 nm is formed from the lower layer to the upper layer so as to be in contact with the upper surface of the p-side ohmic electrode 9 on the surface of the insulating film 10 using a vacuum deposition method. A p-side pad electrode 11 made of a Ti layer, a Pd layer having a thickness of about 100 nm, and an Au layer having a thickness of about 3 μm is formed. Thereafter, the back surface of the n-type GaN substrate 1 is polished so that the thickness of the n-type GaN substrate 1 is about 100 μm.

Next, in the first reference embodiment, a thickness of about 250 nm is formed on the entire back surface of the n-type GaN substrate 1 using a plasma CVD method, an SOG (spin-on-glass) method (coating method), or an electron beam evaporation method. An SiO ₂ film (not shown) having a film is formed. Thereafter, by removing the SiO ₂ film located in the region other than the region 8 where dislocations are concentrated on the back surface of the n-type GaN substrate 1, as shown in FIG. 12, the thickness is about 250 nm and the width is about 40 μm. An insulating film 12 made of a SiO ₂ film is formed. Thereby, the region 8 where dislocations are concentrated on the back surface of the n-type GaN substrate 1 is covered with the insulating film 12.

  Thereafter, as shown in FIG. 1, a region other than the region 8 where dislocations are concentrated on the back surface of the n-type GaN substrate 1 is brought into contact with the back surface of the n-type GaN substrate 1 by using a vacuum deposition method. At the same time, an n-side electrode 13 is formed so as to cover the insulating film 12. When the n-side electrode 13 is formed, an Al layer having a thickness of about 10 nm, a Pt layer having a thickness of about 20 nm, and a thickness of about 300 nm are arranged in order from the side closer to the back surface of the n-type GaN substrate 1. And an Au layer. Finally, a scribe line (not shown) is formed from the side where the p-side pad electrode 11 of the element is formed, and then the element is cleaved along the scribe line into each chip, thereby nitriding according to the first reference embodiment. A physical semiconductor laser element is formed.

(Second reference form)
FIG. 13 is a cross-sectional view showing the structure of a nitride-based semiconductor laser device (semiconductor device) according to the second embodiment of the present invention. Referring to FIG. 13, in the second reference embodiment, unlike the first reference embodiment, the predetermined regions at the ends of n-type GaN substrate 1 and nitride-based semiconductor layers (2 to 5) are removed. For this reason, there is no region 8 where dislocations are concentrated as in the first embodiment shown in FIG. Further, an Al layer having a thickness of about 10 nm is formed on the back surface of the n-type GaN substrate 1 in order from the back surface of the n-type GaN substrate 1 so as to be in contact with the entire back surface of the n-type GaN substrate 1. In addition, an n-side electrode 33 made of a Pt layer having a thickness of about 20 nm and an Au layer having a thickness of about 300 nm is formed. The n-side electrode 33 is an example of the “back side electrode” in the present invention. In addition, the other structure of 2nd reference form is the same as that of the said 1st reference form.

  14 and 15 are cross-sectional views for explaining the 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 according to the second embodiment is now described with reference to FIGS.

  First, using the same manufacturing process as in the first embodiment shown in FIGS. 3 to 11, up to the p-side pad electrode 11 is formed, and then the back surface of the n-type GaN substrate 1 is polished. Thereafter, an n-side electrode 33 having the same thickness and composition as in the first reference embodiment is formed on the back surface of the n-type GaN substrate 1 so as to be in contact with the entire back surface of the n-type GaN substrate 1. The structure shown in FIG. 14 is obtained.

  Finally, in the second reference embodiment, the scribe line 40 is formed from the side where the p-side pad electrode 11 of the element is formed so as to sandwich the region 8 where dislocations are concentrated. Specifically, a scribe line is formed at a position of about 10 μm from a center line (not shown) between adjacent elements. Thereafter, as shown in FIG. 15, the concentration of dislocations extending along the scribe line 40 (see FIG. 14) from the back surface of the n-type GaN substrate 1 to the surface of the flat portion other than the convex portion of the p-type cladding layer 5. The element is cleaved into each chip so that the region 8 being removed is removed with the same width. Thus, the nitride-based semiconductor laser device according to the second embodiment shown in FIG. 13 is formed.

  In the manufacturing process of the second reference embodiment, as described above, the dislocation-concentrated region 8 extending from the back surface of the n-type GaN substrate 1 to the surface of the flat portion other than the convex portion of the p-type cladding layer 5 has the same width. By cleaving the element into each chip so as to be removed, it is possible to easily suppress the occurrence of leakage current due to current flowing through the region 8 where dislocations are concentrated. As a result, since the optical output during constant current driving of the element can be easily stabilized, a nitride semiconductor laser element with stable operation can be easily manufactured.

  Further, it is possible to easily suppress the light generated in the light emitting layer 4 from being absorbed in the region 8 where dislocations are concentrated. As a result, it is possible to easily suppress the light absorbed in the region 8 where dislocations are concentrated from being emitted again at an unintended wavelength, thereby suppressing the deterioration in color purity caused by such re-emission. can do.

(3rd reference form)
FIG. 16 is a cross-sectional view showing the structure of a light emitting diode element (semiconductor element) according to the third embodiment of the present invention. FIG. 17 is an enlarged cross-sectional view showing details of the light emitting layer of the light emitting diode device according to the third embodiment shown in FIG. With reference to FIGS. 16 and 17, in the third reference embodiment, an example in which the present invention is applied to a light emitting diode element, unlike the first reference embodiment, will be described.

  That is, in the third embodiment, as shown in FIG. 16, an n-type cladding layer 52 made of n-type GaN doped with Si having a thickness of about 5 μm is formed on an n-type GaN substrate 1. . The n-type cladding layer 52 is an example of the “semiconductor element layer” in the present invention.

On the n-type cladding layer 52, a light emitting layer 53 is formed. As shown in FIG. 17, the light emitting layer 53 includes six barrier layers 53a made of undoped GaN having a thickness of about 5 nm and five layers made of undoped In _0.35 Ga _0.65 N having a thickness of about 5 nm. Are formed by MQW active layers 53c in which well layers 53b are alternately stacked and a protective layer 53d made of undoped GaN having a thickness of about 10 nm. The light emitting layer 53 is an example of the “semiconductor element layer” in the present invention.

As shown in FIG. 16, a p-type clad layer 54 made of p-type Al _0.05 Ga _0.95 N doped with Mg having a thickness of about 0.15 μm is formed on the light emitting layer 53. ing. A p-type contact layer 55 made of p-type GaN doped with Mg and having a thickness of about 0.3 μm is formed on the p-type cladding layer 54. The p-type cladding layer 54 and the p-type contact layer 55 are examples of the “semiconductor element layer” in the present invention.

  In the vicinity of the end portions of the n-type GaN substrate 1 and the nitride-based semiconductor layers (52 to 55), dislocations extending from the back surface of the n-type GaN substrate 1 to the upper surface of the p-type contact layer 55 are concentrated. 56 is formed.

Here, the light emitting diode device according to the third reference embodiment, the region 56 are concentrated dislocations on the p-type contact layer 55, made of SiO ₂ film having a width of thickness about 40μm to about 250nm insulating film 57 Is formed. A p-side ohmic electrode 58 is formed on the p-type contact layer 55 so as to be in contact with a region other than the region 56 where dislocations are concentrated on the upper surface of the p-type contact layer 55 and to cover the insulating film 57. Has been. The p-side ohmic electrode 58 includes a Pt layer having a thickness of about 5 nm, a Pd layer having a thickness of about 100 nm, and an Au layer having a thickness of about 150 nm from the lower layer to the upper layer. The p-side ohmic electrode 58 is an example of the “surface-side electrode” in the present invention. On the p-side ohmic electrode 58, a p layer comprising a Ti layer having a thickness of about 100 nm, a Pd layer having a thickness of about 100 nm, and an Au layer having a thickness of about 3 μm from the lower layer to the upper layer. A side pad electrode 59 is formed.

  In the third reference embodiment, the n-side ohmic transparent electrode 60 is disposed on the back surface of the n-type GaN substrate 1 so as to contact a region other than the region 56 where dislocations are concentrated on the back surface of the n-type GaN substrate 1. Is formed. The n-side ohmic transparent electrode 60 includes an Al layer having a thickness of about 5 nm, a Pt layer having a thickness of about 15 nm, and an Au layer having a thickness of about 40 nm in order from the side closer to the back surface of the n-type GaN substrate 1. It consists of. The distance W between the end face of the n-side ohmic transparent electrode 60 and the end face of the element is about 40 μm. The n-side transparent electrode 60 is an example of the “back side electrode” in the present invention. Then, in a predetermined region on the back surface of the n-side ohmic transparent electrode 60, a Ti layer having a thickness of about 100 nm, a Pd layer having a thickness of about 100 nm, in order from the side close to the back surface of the n-side ohmic transparent electrode 60, An n-side pad electrode 61 made of an Au layer having a thickness of about 3 μm is formed.

  In the third reference embodiment, as described above, the insulating film 57 is formed in the region where dislocations are concentrated on the p-type contact layer 55, and the region where dislocations are concentrated on the upper surface of the p-type contact layer 55. By forming the p-side ohmic electrode 58 so as to be in contact with a region other than the region 56, the region 56 where dislocations are concentrated on the upper surface of the p-type contact layer 55 is covered with the insulating film 57 so as not to be exposed. In addition, it is possible to easily suppress the occurrence of leakage current caused by current flowing through the region 56 where dislocations are concentrated on the upper surface of the p-type contact layer 55. Further, the n-side ohmic transparent electrode 60 is formed on the back surface of the n-type GaN substrate 1 so as to be in contact with a region other than the region 56 where dislocations are concentrated on the back surface of the n-type GaN substrate 1. It is also possible to suppress the occurrence of leakage current due to current flowing through the region 56 where dislocations are concentrated on the back surface of the GaN substrate 1. As a result, since the optical output during constant current driving of the element can be easily stabilized, the operation of the semiconductor element can be easily stabilized. In addition, since current flowing in the region 56 where dislocations are concentrated can be reduced, unnecessary light emission from the region 56 where dislocations are concentrated can be reduced.

  In the third reference embodiment, the n-side pad electrode formed on the n-side ohmic transparent electrode 60 by setting the distance W between the end face of the n-side ohmic transparent electrode 60 and the end face of the element to about 40 μm. When the solder is fused to 61, the solder can be prevented from flowing to the side surface of the element. Thereby, generation | occurrence | production of the short circuit defect of an element can be suppressed.

  18 to 21 are cross-sectional views for explaining a manufacturing process of the light-emitting diode device according to the third embodiment shown in FIG. Next, with reference to FIGS. 16-21, the manufacturing process of the light emitting diode element by a 3rd reference form is demonstrated.

  First, as shown in FIG. 18, an n-type cladding layer 52, a light emitting layer 53, a p-type cladding layer 54 and a p-type contact layer 55 are sequentially grown on the n-type GaN substrate 1 using MOCVD.

Specifically, about 1000 ° C. ~ about 1200 ° C. The substrate temperature (e.g., about 1150 ° C.) while maintaining the growth temperature of the carrier gas consisting of _{H 2} and _{N 2 (H 2} content: 50%) And n-type cladding made of n-type GaN doped with Si having a thickness of about 5 μm on the n-type GaN substrate 1 using a source gas made of NH ₃ and TMGa and a dopant gas made of SiH ₄ Layer 52 is grown at a growth rate of about 3 μm / h.

Next, as shown in FIG. 17, in the state where the substrate temperature is maintained at a growth temperature of about 700 ° C. to about 1000 ° C. (for example, about 850 ° C.), a carrier gas composed of H ₂ and N ₂ (containing H _2). And an undoped GaN having a thickness of about 5 nm on the n-type cladding layer 52 (see FIG. 18) using a source gas composed of NH ₃ , TEGa, and TMIn. Six barrier layers 53a and five well layers 53b made of undoped In _0.35 Ga _0.65 N having a thickness of about 5 nm are alternately grown at a growth rate of about 0.4 nm / s. Thus, the MQW active layer 53c is formed. Subsequently, a protective layer 53d made of undoped GaN having a thickness of about 10 nm is grown at a growth rate of about 0.4 nm / s. Thereby, the light emitting layer 53 composed of the MQW active layer 53c and the protective layer 53d is formed.

Next, as shown in FIG. 18, about 1000 ° C. ~ about 1200 ° C. The substrate temperature (e.g., about 1150 ° C.) while maintaining the growth temperature of the carrier gas _{(H 2} content consisting of _{H 2} and _{N 2} : About 1% to about 3%), a source gas composed of NH ₃ , TMGa and TMAl, and a dopant gas composed of Cp ₂ Mg, and Mg having a thickness of about 0.15 μm on the light emitting layer 53 A p-type cladding layer 54 made of p-type Al _0.05 Ga _0.95 N doped with is grown at a growth rate of about 3 μm / h. Subsequently, the source gas is changed to NH ₃ and TMGa, and a p-type contact layer 55 made of p-type GaN doped with Mg having a thickness of about 0.3 μm is formed on the p-type cladding layer 54 at about 3 μm / Grow at a growth rate of h.

At this time, dislocations of the n-type GaN substrate 1 propagate to form a region 56 where dislocations are concentrated extending from the back surface of the n-type GaN substrate 1 to the upper surface of the p-type contact layer 55. Further, by reducing the H ₂ content of the carrier gas composed of H ₂ and N ₂ , the Mg dopant can be activated without annealing in a nitrogen gas atmosphere.

Next, in the third reference embodiment, a SiO ₂ film having a thickness of about 250 nm is formed on the entire surface of the p-type contact layer 55 by using a plasma CVD method, an SOG method (coating method), or an electron beam evaporation method. (Not shown). Thereafter, by removing the SiO ₂ film located in the region other than the region 56 where dislocations are concentrated on the p-type contact layer 55, a thickness of about 250 nm and a width of about 40 μm are obtained as shown in FIG. An insulating film 57 is formed. As a result, the region 56 where dislocations are concentrated on the upper surface of the p-type contact layer 55 is covered with the insulating film 57.

  Next, as shown in FIG. 20, a region other than the region 56 where dislocations are concentrated on the upper surface of the p-type contact layer 55 is contacted on the p-type contact layer 55 by using a vacuum deposition method, and insulation is performed. A p-side ohmic electrode 58 is formed so as to cover the film 57. When the p-side ohmic electrode 58 is formed, a Pt layer having a thickness of about 5 nm, a Pd layer having a thickness of about 100 nm, and an Au layer having a thickness of about 150 nm are formed from the lower layer to the upper layer. Form. Next, on the p-side ohmic electrode 58, a Ti layer having a thickness of about 100 nm, a Pd layer having a thickness of about 100 nm, and a thickness of about 3 μm are formed on the p-side ohmic electrode 58 using a vacuum deposition method. A p-side pad electrode 59 made of the Au layer is formed. Thereafter, the back surface of the n-type GaN substrate 1 is polished so that the thickness of the n-type GaN substrate 1 is about 100 μm.

  Next, in the third reference embodiment, an Al layer having a thickness of about 5 nm is formed on the entire back surface of the n-type GaN substrate 1 in order from the side closer to the back surface of the n-type GaN substrate 1 by using vacuum deposition. Then, a metal layer (not shown) made of a Pt layer having a thickness of about 15 nm and an Au layer having a thickness of about 40 nm is formed. Thereafter, by removing the metal layer located in the region other than the region 56 where the dislocations are concentrated on the back surface of the n-type GaN substrate 1, an n-side ohmic transparent electrode 60 is formed as shown in FIG. At this time, the metal layer is removed so that the distance W between the end face of the n-side ohmic transparent electrode 60 and the end face of the element is about 40 μm.

  Thereafter, as shown in FIG. 16, a thickness of about 100 nm is sequentially formed in a predetermined region on the back surface of the n-side ohmic transparent electrode 60 from the side closer to the back surface of the n-side ohmic transparent electrode 60 by using a vacuum deposition method. An n-side pad electrode 61 made of a Ti layer having a thickness, a Pd layer having a thickness of about 100 nm, and an Au layer having a thickness of about 3 μm is formed. Finally, a scribe line (not shown) is formed from the side of the element where the p-side pad electrode 59 is formed, and then the element is cleaved along each scribe line into each chip, thereby emitting light according to the third reference embodiment. A diode element is formed.

(4th reference form)
FIG. 22 is a sectional view showing the structure of a nitride-based semiconductor laser device (semiconductor device) according to the fourth embodiment of the present invention. Referring to FIG. 22, in the fourth reference embodiment, unlike the first reference embodiment, Ge having a thickness of about 0.4 μm is doped on the surface of the flat portion other than the convex portion of p-type cladding layer 5. An n-type current blocking layer 80 made of the n-type Al _0.12 Ga _0.88 N is formed.

  In the fourth embodiment, the n-type GaN substrate 1 and the nitride-based semiconductor layers (2 to 5 and 80) are located near the end portions of the n-type GaN substrate 1 from the back surface of the n-type GaN substrate 1. A region 8 where dislocations are concentrated extending to the upper surface is formed. Further, on the n-type current blocking layer 80, a Pt layer having a thickness of about 5 nm from the lower layer to the upper layer so as to contact the upper surface of the p-type contact layer 6 constituting the ridge portion 7, and about 100 nm. A p-side ohmic electrode 79 made of a Pd layer having a thickness of approximately 150 nm and an Au layer having a thickness of approximately 150 nm is formed. In addition, on the p-side ohmic electrode 79, from the lower layer to the upper layer, a Ti layer having a thickness of about 100 nm, a Pd layer having a thickness of about 100 nm, and an Au layer having a thickness of about 3 μm are formed. A side pad electrode 81 is formed. The n-type current blocking layer 80 is an example of the “semiconductor element layer” in the present invention, and the p-side ohmic electrode 79 is an example of the “surface-side electrode” in the present invention.

  Here, in the fourth reference embodiment, as in the first reference embodiment, a thickness of about 250 nm and a width of about 40 μm are formed so as to cover the region 8 where dislocations are concentrated on the back surface of the n-type GaN substrate 1. An insulating film 12 made of a SiN film is formed. On the back surface of the n-type GaN substrate 1, an n-side electrode 13 is in contact with a region other than the region 8 where dislocations are concentrated on the back surface of the n-type GaN substrate 1 and covers the insulating film 12. Is formed.

  The other configurations of the fourth reference embodiment are the same as those of the first reference embodiment.

In the fourth reference embodiment, as described above, the nitride-based semiconductor laser device in which the n-type current blocking layer 80 made of n-type Al _0.12 Ga _0.88 N is formed as the current blocking layer is also described above. The same effect as in the first embodiment can be obtained. That is, the insulating film 12 is formed in the region 8 where dislocations are concentrated on the back surface of the n-type GaN substrate 1, and the region other than the region 8 where dislocations are concentrated on the back surface of the n-type GaN substrate 1 is contacted. Thus, by forming the n-side electrode 13, the region 8 where dislocations are concentrated on the back surface of the n-type GaN substrate 1 is covered so as not to be exposed by the insulating film 12. It is possible to easily suppress the occurrence of a leakage current due to the current flowing in the region 8 where dislocations are concentrated on the back surface. As a result, since the optical output during constant current driving of the element can be easily stabilized, the operation of the semiconductor element can be easily stabilized. However, in the fourth reference embodiment, since the region 8 where dislocations on the upper surface of the n-type current blocking layer 80 are concentrated is in contact with the p-side ohmic electrode 79, a leakage current is generated as compared with the first reference embodiment. Cheap.

  23 to 26 are cross-sectional views for explaining the manufacturing process of the nitride-based semiconductor laser device according to the fourth embodiment shown in FIG. Next, with reference to FIGS. 22 to 26, a manufacturing process for the nitride-based semiconductor laser device according to the fourth embodiment will be described.

  First, the p-type contact layer 6 is formed by using the same manufacturing process as in the first embodiment shown in FIGS. 3 to 7, and then annealed in a nitrogen gas atmosphere. Next, as shown in FIG. 23, after a SiN layer 91 having a thickness of about 200 nm is formed in a predetermined region on the p-type contact layer 6 by using plasma CVD, about 250 nm is formed on the SiN layer 91. A Ni layer 92 having a thickness of 1 mm is formed. At this time, the SiN layer 91 and the Ni layer 92 are formed in a stripe shape (elongated shape) having a width of about 1.5 μm.

Next, as shown in FIG. 24, a thickness of about 300 nm is etched from the upper surfaces of the p-type contact layer 6 and the p-type cladding layer 5 by using dry etching with a Cl ₂ gas, using the Ni layer 92 as a mask. . As a result, a striped (elongated) ridge portion 7 is formed which is composed of the convex portion of the p-type cladding layer 5 and the p-type contact layer 6 and extends in a predetermined direction. Thereafter, the Ni layer 92 is removed.

Next, as shown in FIG. 25, the MOCVD method is used to form a thickness of about 0.4 μm on the surface of the flat portion other than the convex portion of the p-type cladding layer 5 using the SiN layer 91 as a selective growth mask. An n-type current blocking layer 80 made of n-type Al _0.12 Ga _0.88 N doped with Ge is formed. At this time, since dislocations on the surface of the flat portion other than the convex portion of the p-type cladding layer 5 propagate, a region 8 in which dislocations extending from the back surface of the n-type GaN substrate 1 to the upper surface of the n-type current blocking layer 80 is concentrated. Is formed. Thereafter, the SiN layer 91 is removed.

  Next, as shown in FIG. 26, from the lower layer to the upper layer, the upper surface of the p-type contact layer 6 constituting the ridge portion 7 is contacted on the n-type current blocking layer 80 by using a vacuum deposition method. Thus, a p-side ohmic electrode 79 made of a Pt layer having a thickness of about 5 nm, a Pd layer having a thickness of about 100 nm, and an Au layer having a thickness of about 150 nm is formed. Thereafter, on the p-side ohmic electrode 79, from the lower layer toward the upper layer, a Ti layer having a thickness of about 100 nm, a Pd layer having a thickness of about 100 nm, and an Au layer having a thickness of about 3 μm are formed. A pad electrode 81 is formed. Thereafter, the back surface of the n-type GaN substrate 1 is polished so that the thickness of the n-type GaN substrate 1 is about 100 μm.

  Next, by using a manufacturing process similar to that of the first reference embodiment shown in FIG. 12, as shown in FIG. 22, the region 8 where dislocations are concentrated on the back surface of the n-type GaN substrate 1 is covered. An insulating film 12 is formed. Thereafter, the insulating film 12 is brought into contact with a region other than the region 8 where dislocations are concentrated on the back surface of the n-type GaN substrate 1 on the back surface of the n-type GaN substrate 1 by using a vacuum deposition method. An n-side electrode 13 is formed so as to cover. Finally, after forming a scribe line (not shown) from the side where the p-side pad electrode 81 of the element is formed, the element is cleaved along the scribe line into each chip, thereby nitriding according to the fourth reference embodiment. A physical semiconductor laser element is formed.

(5th reference form)
FIG. 27 is a cross-sectional view showing the structure of a light emitting diode element (semiconductor element) according to the fifth embodiment of the present invention. Referring to FIG. 27, in the fifth reference embodiment, unlike the third reference embodiment, a thickness of about 250 nm and a width of about 40 μm are formed in a region 56 where dislocations are concentrated on the back surface of n-type GaN substrate 1. An insulating film 100 made of a SiO ₂ film is formed.

  Further, in the fifth reference embodiment, on the back surface of the n-type GaN substrate 1, a region other than the region 56 where dislocations are concentrated on the back surface of the n-type GaN substrate 1 is contacted and the insulating film 100 is covered. An n-side ohmic transparent electrode 110 having the same thickness and composition as the third reference embodiment is formed. The n-side ohmic transparent electrode 110 includes an Al layer having a thickness of about 5 nm, a Pt layer having a thickness of about 15 nm, and an Au layer having a thickness of about 40 nm in order from the side closer to the back surface of the n-type GaN substrate 1. It consists of. In a predetermined region on the back surface of the n-side ohmic transparent electrode 110, a Ti layer having a thickness of about 100 nm, a Pd layer having a thickness of about 100 nm, An n-side pad electrode 111 made of an Au layer having a thickness of 3 μm is formed. The n-side ohmic transparent electrode 110 is an example of the “back side electrode” in the present invention. The other configurations of the fifth reference embodiment are the same as those of the third reference embodiment.

  In the fifth reference embodiment, as described above, the insulating film 100 is formed in the region 56 where the dislocations are concentrated on the back surface of the n-type GaN substrate 1, and the dislocations on the back surface of the n-type GaN substrate 1 are concentrated. By forming the n-side ohmic transparent electrode 110 so as to be in contact with a region other than the region 56, the region 56 where dislocations on the back surface of the n-type GaN substrate 1 are concentrated is not exposed by the insulating film 100. Therefore, it is possible to easily suppress the occurrence of leakage current due to the current flowing through the region 56 where dislocations are concentrated on the back surface of the n-type GaN substrate 1. Similarly to the third embodiment, the region 56 where dislocations are concentrated on the upper surface of the p-type contact layer 55 is covered with the insulating film 57 so as not to be exposed. It is also possible to easily suppress the occurrence of leakage current caused by current flowing through the concentrated region 56. As a result, since the optical output during constant current driving of the element can be more easily stabilized, the operation of the semiconductor element can be more easily stabilized. In addition, since current flowing in the region 56 where dislocations are concentrated can be reduced, unnecessary light emission from the region 56 where dislocations are concentrated can be reduced.

  FIG. 28 is a cross-sectional view for explaining a manufacturing process for the light-emitting diode device according to the fifth embodiment shown in FIG. Next, with reference to FIGS. 27 and 28, a manufacturing process of the light-emitting diode element according to the fifth embodiment will be described.

First, using a manufacturing process similar to that of the third reference embodiment shown in FIGS. 18 to 20, after forming the p-side pad electrode 59, the back surface of the n-type GaN substrate 1 is polished. Next, in the fifth reference embodiment, SiO ₂ having a thickness of about 250 nm is formed on the entire back surface of the n-type GaN substrate 1 by using a plasma CVD method, an SOG method (coating method), or an electron beam evaporation method. A film (not shown) is formed. Thereafter, by removing the SiO ₂ film located in the region other than the region 56 where the dislocations are concentrated on the back surface of the n-type GaN substrate 1, as shown in FIG. 28, the thickness is about 250 μm and the width is about 40 μm. forming an insulating film 100 of SiO ₂ having and. As a result, the region 56 where dislocations are concentrated on the back surface of the n-type GaN substrate 1 is covered with the insulating film 100. Next, using vacuum evaporation, the back surface of the n-type GaN substrate 1 is contacted with a region other than the region 56 where dislocations are concentrated on the back surface of the n-type GaN substrate 1 and the insulating film 100 is covered. Next, the n-side ohmic transparent electrode 110 is formed. When the n-side ohmic transparent electrode 110 is formed, the Al layer having a thickness of about 5 nm, the Pt layer having a thickness of about 15 nm, and the thickness of about 40 nm are arranged in order from the side closer to the back surface of the n-type GaN substrate 1. And an Au layer having a thickness of 5 mm.

  Thereafter, as shown in FIG. 27, a thickness of about 100 nm is formed in a predetermined region on the back surface of the n-side ohmic transparent electrode 110 in order from the side closer to the back surface of the n-side ohmic transparent electrode 110 using a vacuum deposition method. An n-side pad electrode 111 made of a Ti layer having a thickness, a Pd layer having a thickness of about 100 nm, and an Au layer having a thickness of about 3 μm is formed. Finally, a scribe line (not shown) is formed from the side where the p-side pad electrode 59 of the element is formed, and then the element is cleaved along the scribe line into each chip, thereby emitting light according to the fifth reference embodiment. A diode element is formed.

(6th reference form)
FIG. 29 is a cross-sectional view showing the structure of a nitride-based semiconductor laser device (semiconductor device) according to the sixth reference embodiment of the present invention. Referring to FIG. 29, in the sixth reference embodiment, unlike the first reference embodiment, ions having a depth reaching the n-type cladding layer 3 from the surface of the flat portion other than the convex portion of the p-type cladding layer 5. The injection layer 120 is provided in the region 8 where dislocations are concentrated. Since the ion implantation layer 120 is formed by ion implantation of impurities such as carbon (C), the region where the ion implantation layer 120 is provided becomes a high resistance region. The ion implantation layer 120 is an example of the “high resistance region” in the present invention. The remaining configuration of the sixth reference embodiment is the same as that of the first reference embodiment.

  In the sixth reference embodiment, as described above, dislocations are concentrated on the ion implantation layer 120 having a depth reaching the n-type cladding layer 3 from the surface of the flat portion other than the convex portion of the p-type cladding layer 5. By providing the region 8 in the region 8 where dislocations are concentrated on the surface of the flat portion other than the convex portion of the p-type cladding layer 5, current does not easily flow through the ion implantation layer 120. It is possible to suppress the occurrence of leakage current due to current flowing in the region 8 where dislocations are concentrated on the surface of the flat portion other than the convex portion. As a result, since the optical output during constant current driving of the element can be easily stabilized, the operation of the semiconductor element can be easily stabilized.

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

Next, as a manufacturing process of the nitride-based semiconductor laser device according to the sixth reference embodiment, the p-type cladding layer 5 is formed after the manufacturing process of the first reference embodiment shown in FIG. Carbon (C) is ion-implanted at about 150 keV into the region 8 where dislocations are concentrated on the surface of the flat part other than the convex part. Thereby, the ion implantation depth (thickness) reaching the n-type clad layer 3 from the surface of the flat portion other than the convex portion of the p-type clad layer 5 and also arranged in the region 8 where dislocations are concentrated. An injection layer 120 is formed. In addition, as ion implantation conditions, it is preferable that the dose is about 1 × 10 ¹⁴ cm ⁻² or more.

(First embodiment)
FIG. 30 is a cross-sectional view showing the structure of the nitride-based semiconductor laser device (semiconductor device) according to the first embodiment of the present invention. Referring to FIG. 30, in the first embodiment, in the structure of the fourth reference embodiment (see FIG. 22), the depth reaches from the upper surface of n-type current blocking layer 80 to the upper surface of n-type cladding layer 3. The recess 130 is provided in a region inside the region 8 where dislocations are concentrated (a range from about 50 μm to about 100 μm from both ends of the element). In addition, in a region inside the recess 130 on the n-type current blocking layer 80, a Pt layer having a thickness of about 5 nm from the lower layer to the upper layer so as to be in contact with the upper surface of the p-type contact layer 6; A p-side ohmic electrode 149 made of a Pd layer having a thickness of about 100 nm and an Au layer having a thickness of about 150 nm is formed. In addition, on the p-side ohmic electrode 149, from the lower layer to the upper layer, a Ti layer having a thickness of about 100 nm, a Pd layer having a thickness of about 100 nm, and an Au layer having a thickness of about 3 μm are formed. A side pad electrode 151 is formed. The p-side ohmic electrode 149 is an example of the “surface-side electrode” in the present invention. In addition, the other structure of 1st Embodiment is the same as that of the said 4th reference form.

  In the first embodiment, as described above, the recess 130 having a depth reaching the upper surface of the n-type cladding layer 3 from the upper surface of the n-type current blocking layer 80 is formed in a region inside the region 8 where dislocations are concentrated. The p-side ohmic electrode is provided in a range of about 50 μm to about 100 μm from both ends, and is in contact with the upper surface of the p-type contact layer 6 in a region inside the recess 130 on the n-type current blocking layer 80. By forming 149, it is possible to suppress the occurrence of leakage current due to current flowing in the region 8 where dislocations are concentrated on the upper surface of the n-type current blocking layer 80. As a result, the light output during constant current driving of the element can be stabilized, so that the operation of the semiconductor element can be stabilized. Moreover, since the region 8 and the concentrated region 8 from the region 8 where the dislocations are concentrated in the light emitting layer 4, the p-type cladding layer 5, and the n-type current blocking layer 80 are separated by the recess 130. It is possible to suppress the light generated in the light emitting layer 4 on the inner side of the region 8 where the concentration is concentrated from being absorbed in the region 8 where dislocations are concentrated. As a result, it is possible to suppress the light absorbed in the region 8 where dislocations are concentrated from being emitted again at an unintended wavelength. Therefore, it is possible to suppress the deterioration in color purity caused by such re-emission. it can.

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

  Next, as a manufacturing process of the nitride-based semiconductor laser device according to the first embodiment, after forming the n-type current blocking layer 80 in the manufacturing process of the fourth reference embodiment shown in FIG. 25, RIE (Reactive Ion Etching) is performed. (Reactive ion etching) method, a recess 130 having a depth reaching the upper surface of the n-type cladding layer 3 from the upper surface of the n-type current blocking layer 80 in a region inside the region 8 where dislocations are concentrated. Form. Then, a metal layer (not shown) constituting the p-side ohmic electrode 149 and the p-side pad electrode 151 is formed on the entire surface including the inner surface of the recess 130 by using a vacuum deposition method. Thereafter, the region 8 where dislocations are concentrated on the n-type current blocking layer 80 and the metal layer located on the inner surface of the recess 130 are removed. Thus, the p-side ohmic electrode 149 is formed in the region inside the recess 130 on the n-type current blocking layer 80 so as to be in contact with the upper surface of the p-type contact layer 6, and on the p-side ohmic electrode 149. The p-side pad electrode 151 is formed.

  FIG. 31 is a cross-sectional view showing the structure of the nitride-based semiconductor laser device according to the first modification of the first embodiment shown in FIG. Referring to FIG. 31, in the nitride-based semiconductor laser device according to the first modification of the first embodiment, the depth of the recess 160 provided in the region inside the region 8 where dislocations are concentrated is set. And reaches the n-type cladding layer 3 from the upper surface of the n-type current blocking layer 80. Even if comprised in this way, the effect similar to the said 1st Embodiment is acquired.

  FIG. 32 is a cross-sectional view showing the structure of the nitride-based semiconductor laser device according to the second modification of the first embodiment shown in FIG. Referring to FIG. 32, in the nitride-based semiconductor laser device according to the second modification of the first embodiment, the region 8 and the recess 130 where dislocations are concentrated on the upper surface of n-type current blocking layer 80 are embedded. In addition, an insulating film 170 is formed. In addition, a Pt layer having a thickness of about 5 nm and a Pd layer having a thickness of about 100 nm are formed on the entire surface of the n-type current blocking layer 80, the insulating film 170, and the p-type contact layer 6 from the lower layer to the upper layer. A p-side ohmic electrode 179 made of an Au layer having a thickness of about 150 nm is formed. In addition, on the p-side ohmic electrode 179, from the lower layer to the upper layer, a Ti layer having a thickness of about 100 nm, a Pd layer having a thickness of about 100 nm, and an Au layer having a thickness of about 3 μm are formed. A side pad electrode 181 is formed. Even if comprised in this way, the effect similar to the said 1st Embodiment is acquired.

(7th reference form)
FIG. 33 is a cross-sectional view showing the structure of a nitride-based semiconductor laser device (semiconductor device) according to the seventh embodiment of the present invention. Referring to FIG. 33, in the seventh reference embodiment, in the structure of the fourth reference embodiment (see FIG. 22), ion implantation layer 190 having a depth of about 0.2 μm from the upper surface of n-type current blocking layer 80. Is provided in the region 8 where dislocations are concentrated. Since the ion implantation layer 190 is formed by ion implantation of impurities such as carbon (C), the region where the ion implantation layer 190 is provided is a high resistance region. The ion implantation layer 190 is an example of the “high resistance region” in the present invention. The remaining configuration of the seventh reference embodiment is similar to that of the aforementioned fourth reference embodiment.

  In the seventh reference embodiment, as described above, by providing the ion implantation layer 190 having a depth of about 0.2 μm from the upper surface of the n-type current blocking layer 80 in the region 8 where dislocations are concentrated, In the region 8 where dislocations are concentrated on the upper surface of the current blocking layer 80, current hardly flows due to the ion implantation layer 190, so that current flows in the region 8 where dislocations are concentrated on the upper surface of the n-type current blocking layer 80. It is possible to suppress the occurrence of leak current due to the above. As a result, since the optical output during constant current driving of the element can be easily stabilized, the operation of the semiconductor element can be easily stabilized.

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

Next, as a manufacturing process of the nitride-based semiconductor laser device according to the seventh reference embodiment, the n-type is performed before the step of forming the p-side ohmic electrode 79 (see FIG. 26) in the manufacturing process of the fourth reference embodiment. Carbon (C) is ion-implanted at about 40 keV into the region 8 where dislocations are concentrated on the upper surface of the current blocking layer 80. As a result, as shown in FIG. 33, the ion implantation layer has an ion implantation depth (thickness) of about 0.2 μm from the upper surface of the n-type current blocking layer 80 and is disposed in the region 8 where dislocations are concentrated. 190 is formed. In addition, as ion implantation conditions, it is preferable that the dose is about 1 × 10 ¹⁴ cm ⁻² or more.

(Eighth reference form)
FIG. 34 is a cross-sectional view showing the structure of a nitride-based semiconductor laser device (semiconductor device) according to the eighth reference embodiment of the present invention. In the eighth reference embodiment, unlike the first to seventh reference embodiments and the first embodiment, an example in which a nitride semiconductor layer including a sapphire substrate is used as a substrate of a nitride semiconductor laser element will be described. .

That is, in the eighth reference embodiment, as shown in FIG. 34, an AlGaN layer 201b having a thickness of about 20 nm is formed on a sapphire substrate 201a. A GaN layer 201c having a thickness of about 1 μm is formed on the AlGaN layer 201b. Dislocations propagated in the vertical direction are formed in the entire region of the GaN layer 201c. In a predetermined region on the GaN layer 201c, a mask layer 201d made of SiN or SiO ₂ having a thickness of about 200 nm is formed. This mask layer 201d functions as a selective growth mask in the manufacturing process described later. An undoped GaN layer 201e having a thickness of about 5 μm is formed on the GaN layer 201c so as to cover the mask layer 201d. The substrate 201 of the nitride-based semiconductor laser device according to the eighth reference embodiment includes a sapphire substrate 201a, an AlGaN layer 201b, a GaN layer 201c, a mask layer 201d, and a GaN layer 201e. The GaN layer 201e of the substrate 201 is an example of the “nitride-based semiconductor substrate” in the present invention.

An n-type layer 202 made of n-type GaN doped with Si having a thickness of about 100 nm and a doping amount of about 5 × 10 ¹⁸ cm ⁻³ is formed on the substrate 201. on the n-type layer 202, having a thickness of about 400 nm, n-type Si doped with a carrier concentration of about 5 × ¹⁰ 18 ^{cm -3} doping amount and about 5 × ¹⁰ 18 ^{cm -3} Al _{0 .05} n-type cladding layer 203 made of Ga _0.95 n is formed. On the n-type cladding layer 203, a light emitting layer 204 having the same configuration as the light emitting layer 4 of the first reference embodiment shown in FIG. 2 is formed. The n-type layer 202, the n-type cladding layer 203, and the light emitting layer 204 are examples of the “semiconductor element layer” in the present invention.

On the light emitting layer 204, a p-type Al _0.05 Ga having a convex portion and doped with Mg having a doping amount of about 4 × 10 ¹⁹ cm ⁻³ and a carrier concentration of about 5 × 10 ¹⁷ cm ^−3. _A p-type cladding layer 205 made of _0.95 N is formed. The convex portion of the p-type cladding layer 205 has a width of about 1.5 μm and a height of about 300 nm. Further, the flat portion other than the convex portion of the p-type cladding layer 205 has a thickness of about 100 nm. On the convex portion of the p-type cladding layer 205, Mg having a thickness of about 10 nm and a doping amount of about 4 × 10 ¹⁹ cm ⁻³ and a carrier concentration of about 5 × 10 ¹⁷ cm ⁻³ is doped. A p-type contact layer 206 made of the p-type GaN is formed. The convex portion of the p-type cladding layer 205 and the p-type contact layer 206 form a striped (elongated) ridge portion 207 extending in a predetermined direction. The p-type cladding layer 205 and the p-type contact layer 206 are examples of the “semiconductor element layer” in the present invention.

  Further, by removing a predetermined region from the flat portion other than the convex portion of the p-type cladding layer 205 to the n-type layer 202, a part of the surface of the n-type cladding layer 202 is exposed. In the vicinity of one end of each of the GaN layer 201e and the nitride-based semiconductor layers (202 to 205) constituting the substrate 201, a convex portion of the p-type cladding layer 205 is formed from the interface of the GaN layer 201c on the AlGaN layer 201b side. A region 208 where dislocations are concentrated extending to the surface of the flat portion other than that is formed. Further, the concentration of dislocations extending from the interface on the AlGaN layer 201b side of the GaN layer 201c to the exposed surface of the n-type layer 202 also in the vicinity of the other ends of the GaN layer 201e and the n-type layer 202 constituting the substrate 201. A region 208 is formed.

  Then, on the p-type contact layer 206 constituting the ridge portion 207, from the lower layer to the upper layer, a Pt layer having a thickness of about 5 nm, a Pd layer having a thickness of about 100 nm, and a thickness of about 150 nm are provided. A p-side ohmic electrode 209 made of an Au layer is formed. The p-side ohmic electrode 209 is an example of the “surface-side electrode” in the present invention.

  Here, in the eighth reference embodiment, about 250 nm so that the upper surface of the p-side ohmic electrode 209 and a predetermined region other than the region 208 where dislocations are concentrated on the exposed surface of the n-type layer 202 are exposed. An insulating film 210 made of a SiN film having a thickness of 1 mm is formed. That is, the surface of the region 208 where the p-side and n-side dislocations are concentrated is covered with the insulating film 210.

  Then, on the surface of the insulating film 210 located on the surface of the flat portion other than the convex portion of the p-type cladding layer 205, the upper surface of the p-side ohmic electrode 209 is contacted with the upper layer from the lower layer toward the upper layer. A p-side pad electrode 211 made of a Ti layer having a thickness of 100 nm, a Pd layer having a thickness of about 100 nm, and an Au layer having a thickness of about 3 μm is formed.

  In the eighth reference embodiment, the n-side electrode 212 is formed so as to be in contact with a region other than the region 208 where dislocations are concentrated on the exposed surface of the n-type layer 202. The n-side electrode 212 is composed of an Al layer having a thickness of about 10 nm, a Pt layer having a thickness of about 20 nm, and an Au layer having a thickness of about 300 nm from the lower layer to the upper layer. The n-side electrode 212 is an example of the “surface side electrode” in the present invention.

  In the eighth reference embodiment, as described above, the insulating film 210 is formed so that a predetermined region other than the region 208 where dislocations are concentrated on the exposed surface of the n-type layer 202 is exposed, and the n-type layer is formed. By forming the n-side electrode 212 so as to be in contact with a region other than the region 208 where the dislocations 208 on the exposed surface 202 are concentrated, the dislocations on the exposed surface of the n-type layer 202 are concentrated. Since the region 208 is covered with the insulating film 210 so as not to be exposed, generation of a leak current due to current flowing through the region 208 where dislocations are concentrated on the exposed surface of the n-type layer 202 is easily suppressed. can do. As a result, since the optical output during constant current driving of the element can be easily stabilized, the operation of the semiconductor element can be easily stabilized. Further, unnecessary light emission due to current flowing through the region 208 where dislocations are concentrated can be suppressed.

  35 to 38 are cross-sectional views for explaining the manufacturing process for the nitride-based semiconductor laser device according to the eighth embodiment shown in FIG. Next, with reference to FIGS. 34 to 38, description will be made on a nitride semiconductor laser device manufacturing process according to the eighth embodiment.

First, the formation process of the substrate 201 will be described with reference to FIG. Specifically, as shown in FIG. 35, an AlGaN layer 201b having a thickness of about 20 nm is grown on the sapphire substrate 201a using the MOCVD method with the substrate temperature maintained at about 600 ° C. Thereafter, the substrate temperature is changed to about 1100 ° C., and a GaN layer 201c having a thickness of about 1 μm is grown on the AlGaN layer 201b. At this time, dislocations propagated in the vertical direction are formed in the entire region of the GaN layer 201c. Next, a mask layer 201d made of SiN or SiO ₂ having a thickness of about 200 nm is formed on the GaN layer 201c at a predetermined interval by plasma CVD.

  Next, using the HVPE method, an undoped GaN layer 201e having a thickness of about 5 μm is laterally formed on the GaN layer 201c using the mask layer 201d as a selective growth mask with the substrate temperature maintained at about 1100 ° C. Grow. At this time, the GaN layer 201e selectively grows in the vertical direction on the GaN layer 201c where the mask layer 201d is not formed, and then gradually grows in the horizontal direction. Therefore, a region 208 where dislocations propagated in the vertical direction are concentrated is formed in the GaN layer 201e located on the GaN layer 201c where the mask layer 201d is not formed. On the other hand, in the GaN layer 201e positioned on the mask layer 201d, dislocations are bent in the lateral direction as the GaN layer 201e grows in the lateral direction, so that dislocations propagated in the vertical direction are not easily formed. The sapphire substrate 201a, the AlGaN layer 201b, the GaN layer 201c, the mask layer 201d, and the GaN layer 201e constitute the substrate 201.

  Next, as shown in FIG. 36, an n-type layer 202, an n-type cladding layer 203, a light emitting layer 204, a p-type cladding layer 205, and a p-type contact layer 206 are sequentially grown on the substrate 201 by using MOCVD. Let Then, a striped (elongated) p-side ohmic electrode 209 is formed in a predetermined region on the p-type contact layer 206. After that, by etching a thickness of about 300 nm from the upper surface of the p-type contact layer 206 and the p-type cladding layer 205, the protrusions of the p-type cladding layer 205 and the p-type contact layer 206 are formed. A striped (elongated) ridge 207 extending in the direction is formed.

  Next, as shown in FIG. 37, by etching a predetermined region from the surface of the flat portion other than the convex portion of the p-type cladding layer 205 to the n-type layer 202, a part of the surface of the n-type layer 202 is exposed. Let

  Next, an SiN film (not shown) having a thickness of about 250 nm is formed by plasma CVD so as to cover the entire surface. Thereafter, by removing the SiN film located on the p-side ohmic electrode 209 and the SiN film located in a predetermined region other than the region 208 where dislocations are concentrated on the exposed surface of the n-type layer 202, As shown in FIG. 38, an insulating film 210 is formed.

  Next, as shown in FIG. 34, the p-side ohmic electrode 209 is formed on the surface of the insulating film 210 located on the surface of the flat portion other than the convex portion of the p-type cladding layer 205 by using a vacuum deposition method. A p-side pad electrode 211 is formed so as to be in contact with the upper surface. Thereafter, in the eighth reference embodiment, in a predetermined region on the insulating film 210 located on the exposed surface of the n-type layer 202, other than the region 208 where dislocations on the exposed surface of the n-type layer 202 are concentrated. The n-side electrode 212 is formed so as to be in contact with the region. Finally, a scribe line (not shown) is formed from the side where the p-side pad electrode 211 of the element is formed, and then the element is cleaved along the scribe line into each chip, thereby nitriding according to the eighth reference embodiment. A physical semiconductor laser element is formed.

(9th reference form)
FIG. 39 is a cross-sectional view showing the structure of a nitride-based semiconductor laser device (semiconductor device) according to the ninth reference embodiment of the present invention. Referring to FIG. 39, in the ninth reference embodiment, unlike the first to eighth reference embodiments and the first embodiment, an n-type GaN substrate is used as the substrate and concentration of dislocations in the n-type cladding layer is concentrated. A case will be described in which the thickness of the existing region is made smaller than the thickness of the region other than the region where the dislocations of the n-type cladding layer are concentrated.

In the nitride semiconductor laser device according to the ninth embodiment, as shown in FIG. 39, the n-type GaN has a thickness of about 100 μm and is doped with oxygen having a carrier concentration of about 5 × 10 ¹⁸ cm ^−3. An n-type layer 222 made of n-type GaN doped with Si and having a thickness of about 100 nm and a doping amount of about 5 × 10 ¹⁸ cm ⁻³ is formed on the substrate 221. The n-type GaN substrate 221 has a wurtzite structure and a (0001) plane surface. on the n-type layer 222, having a thickness of about 400 nm, n-type Si doped with a carrier concentration of about 5 × ¹⁰ 18 ^{cm -3} doping amount and about 5 × ¹⁰ 18 ^{cm -3} Al _{0 An} n-type cladding layer 223 made of _.05 Ga _0.95 N is formed. Further, in the vicinity of the ends of the n-type GaN substrate 221, the n-type layer 222, and the n-type cladding layer 223, it extends from the back surface of the n-type GaN substrate 221 to the surface of the n-type cladding layer 223 and has a width of about 10 μm. Dislocation-concentrated regions 228 having stripes are formed in a stripe shape (elongated shape) with a period of about 400 μm. The n-type GaN substrate 221 is an example of the “substrate” in the present invention, and the n-type layer 222 and the n-type cladding layer 223 are examples of the “semiconductor element layer” and the “first semiconductor layer” in the present invention. is there.

  Here, in the ninth reference embodiment, the thickness of the region 228 where the dislocations of the n-type cladding layer 223 are concentrated is smaller than the thickness of the region other than the region 228 where the dislocations of the n-type cladding layer 223 are concentrated. As described above, the n-type cladding layer 223 is removed from the upper surface to a predetermined depth. A light emitting layer 224 having an MQW active layer is formed in a region other than the region 228 where dislocations are concentrated on the n-type cladding layer 223. This light emitting layer 224 is made of each nitride-based semiconductor layer having the same thickness and composition as the light emitting layer 4 of the first reference embodiment shown in FIG. 2, and the region 228 where the dislocations of the n-type cladding layer 223 are concentrated. It has a width (about 7.5 μm) smaller than the width of the other region. The light emitting layer 224 is an example of the “semiconductor element layer” in the present invention.

On the light emitting layer 224, p-type Al _0.05 Ga having a convex portion and doped with Mg having a doping amount of about 4 × 10 ¹⁹ cm ⁻³ and a carrier concentration of about 5 × 10 ¹⁷ cm ^−3. p-type cladding layer 225 made of _0.95 N is formed. The convex portion of the p-type cladding layer 225 has a width of about 1.5 μm and a protruding height of about 300 nm from the upper surface of the flat portion. The flat portion of the p-type cladding layer 225 has a thickness of about 100 nm. On the convex portion of the p-type cladding layer 225, Mg having a thickness of about 10 nm, a doping amount of about 4 × 10 ¹⁹ cm ⁻³ and a carrier concentration of about 5 × 10 ¹⁷ cm ⁻³ is doped. A p-type contact layer 226 made of the p-type GaN is formed. The convex portion of the p-type cladding layer 225 and the p-type contact layer 226 form a striped (elongated) ridge portion 227 extending in a predetermined direction. The p-type cladding layer 225 and the p-type contact layer 226 are examples of the “semiconductor element layer” and the “second semiconductor layer” in the present invention.

  Then, on the p-type contact layer 226 constituting the ridge portion 227, a Pt layer having a thickness of about 5 nm, a Pd layer having a thickness of about 100 nm, and a thickness of about 150 nm are formed from the lower layer to the upper layer. A p-side ohmic electrode 229 made of an Au layer is formed. The p-side ohmic electrode 229 is an example of the “surface-side electrode” in the present invention. Further, an insulating film 230 made of a SiN film having a thickness of about 250 nm is formed on a region other than the surface exposed by removing the n-type cladding layer 223 and the upper surface of the p-side ohmic electrode 229. On the surface of the insulating film 230, a Ti layer having a thickness of about 100 nm, a Pd layer having a thickness of about 100 nm, and a Pd layer having a thickness of about 100 nm from the lower layer to the upper layer so as to be in contact with the upper surface of the p-side ohmic electrode 229, A p-side pad electrode 231 made of an Au layer having a thickness of 3 μm is formed. Also, an Al layer having a thickness of about 10 nm is formed on the back surface of the n-type GaN substrate 221 in order from the back surface of the n-type GaN substrate 221 so as to be in contact with the entire back surface of the n-type GaN substrate 221. In addition, an n-side electrode 232 made of a Pt layer having a thickness of about 20 nm and an Au layer having a thickness of about 300 nm is formed.

  In the ninth reference embodiment, as described above, the thickness of the region 228 where the dislocations of the n-type cladding layer 223 are concentrated is larger than the thickness of the region other than the region 228 where the dislocations of the n-type cladding layer 223 are concentrated. The n-type cladding layer 223 formed through the light-emitting layer 224 and the p-type are formed by reducing the size and forming the light-emitting layer 224 in a region other than the region 228 where dislocations are concentrated on the n-type cladding layer 223. Since the region 228 where dislocations are concentrated is not formed in the pn junction region with the clad layer 225, the occurrence of leakage current due to current flowing through the region 228 where dislocations are concentrated can be suppressed. As a result, since the optical output during constant current driving of the element can be easily stabilized, the operation of the nitride-based semiconductor laser element can be easily stabilized. In addition, since current flowing in the region 228 where dislocations are concentrated can be reduced, unnecessary light emission from the region 228 where dislocations are concentrated can be reduced.

  In the ninth reference embodiment, the light emitting layer 224 is formed through the light emitting layer 224 by making the width of the light emitting layer 224 smaller than the width of the region other than the region 228 where dislocations of the n-type cladding layer 223 are concentrated. Since the pn junction region between the n-type cladding layer 223 and the p-type cladding layer 225 is reduced, the pn junction capacitance between the n-type cladding layer 223 and the p-type cladding layer 225 can be reduced. Thereby, the response speed of the nitride-based semiconductor laser device can be increased.

  40 to 45 are cross-sectional views for explaining a manufacturing process of the nitride-based semiconductor laser device according to the ninth reference embodiment shown in FIG. Next, with reference to FIGS. 39 to 45, a manufacturing process for the nitride-based semiconductor laser device according to the ninth reference embodiment is described.

  First, as shown in FIG. 40, a ridge constituted by the protrusions of the p-type cladding layer 225 and the p-type contact layer 226 using the same manufacturing process as that of the first reference embodiment shown in FIGS. The part 227 and the p-side ohmic electrode 229 are formed. Thereafter, a resist 241 is formed in a predetermined region other than the region 228 where dislocations are concentrated on the flat portion of the p-type cladding layer 225 so as to cover the surfaces of the p-side ohmic electrode 229 and the ridge portion 227.

  Next, as shown in FIG. 41, from the upper surface of the flat portion of the p-type cladding layer 225 to the light emitting layer 224 is etched using the resist 241 as a mask. This removes the region 228 where dislocations of the p-type cladding layer 225 and the light emitting layer 224 are concentrated, and reduces the width of the p-type cladding layer 225 and the light emitting layer 224 by concentrating the dislocations of the n-type cladding layer 223. It is made smaller than the width of the area other than the area 228. Thereafter, the resist 241 is removed.

  Next, as shown in FIG. 42, an SiN film (not shown) having a thickness of about 250 nm is formed so as to cover the entire surface by plasma CVD, and then is formed on the upper surface of the p-side ohmic electrode 229. By removing the positioned SiN film, an insulating film 230 made of a SiN film having a thickness of about 250 nm is formed.

  Next, as shown in FIG. 43, about 100 nm from the lower layer to the upper layer so as to come into contact with the upper surface of the p-side ohmic electrode 229 in a predetermined region on the surface of the insulating film 230 using a vacuum deposition method. A p-side pad electrode 231 made of a Ti layer having a thickness of approximately 100 nm, a Pd layer having a thickness of approximately 100 nm, and an Au layer having a thickness of approximately 3 μm is formed. Then, the back surface of the n-type GaN substrate 221 is polished so that the thickness of the n-type GaN substrate 221 is about 100 μm. Thereafter, using a vacuum deposition method, the surface of the n-type GaN substrate 221 is contacted with the entire back surface of the n-type GaN substrate 221, so that the surface of the n-type GaN substrate 221 is in contact with the back surface. An n-side electrode 232 made of an Al layer having a thickness of approximately 20 nm, a Pt layer having a thickness of approximately 20 nm, and an Au layer having a thickness of approximately 300 nm is formed.

  Next, as shown in FIG. 44, dislocation from the surface of the p-side pad electrode 231 in the boundary region between adjacent elements to a predetermined depth of the insulating film 230 and the n-type cladding layer 223 using the RIE method using chlorine. The region 228 where the concentration is concentrated is removed. As a result, a groove 233 having a width W2 (for example, about 60 μm) larger than the width of the region 228 where dislocations are concentrated is formed in the region 228 where dislocations are concentrated.

  Next, as shown in FIG. 45, a scribe line 234 is formed at the center of the bottom of the groove 233 using diamond points. Thereafter, the elements are separated into chips along the scribe line 234. Thus, the nitride semiconductor laser element according to the ninth reference embodiment shown in FIG. 39 is formed.

(10th reference form)
FIG. 46 is a cross-sectional view showing the structure of a nitride-based semiconductor laser device (semiconductor device) according to the tenth reference embodiment of the present invention. Referring to FIG. 46, in the tenth reference embodiment, unlike the ninth reference embodiment, the light emitting layer 224a has the same width as the n-type cladding layer 223a. Further, the n-type GaN substrate 221a has a thickness of the region 228 where dislocations are concentrated so that the thickness of the region other than the region 228 where the dislocations are concentrated in the n-type GaN substrate 221a is smaller. A predetermined depth is removed from the upper surface of 221a. Then, an n-type layer 222a, an n-type clad layer 223a, a light emitting layer 224a, a p-type clad layer 225a, and a p-type contact layer 226a are sequentially formed in regions other than the region 228 where dislocations are concentrated on the n-type GaN substrate 221a. Is formed.

  An insulating film 260 is formed on the flat portion of the p-type cladding layer 225a and on the side surfaces of the ridge portion 227a and the p-side ohmic electrode 229a. A p-side pad electrode 261 is formed on the surface of the insulating film 260 so as to be in contact with the upper surface of the p-side ohmic electrode 229a. Note that the n-type GaN substrate 221a, the n-type layer 222a, the n-type cladding layer 223a, the light emitting layer 224a, the p-type cladding layer 225a, the p-type contact layer 226a, and the p-side ohmic electrode 229a are each of the ninth reference embodiment. The n-type GaN substrate 221, the n-type layer 222, the n-type cladding layer 223, the light emitting layer 224, the p-type cladding layer 225, the p-type contact layer 226, and the p-side ohmic electrode 229 have the same thickness and composition. The insulating film 260 and the p-side pad electrode 261 have the same thickness and composition as the insulating film 230 and the p-side pad electrode 231 of the ninth reference embodiment, respectively.

  The other configurations of the tenth reference embodiment are the same as those of the ninth reference embodiment.

  In the tenth reference embodiment, as described above, the thickness of the region 228 where the dislocations of the n-type GaN substrate 221a are concentrated is larger than the thickness of the region other than the region 228 where the dislocations of the n-type GaN substrate 221a are concentrated. The n-type layer 222a, the n-type cladding layer 223a, the light emitting layer 224a, the p-type cladding layer 225a, and the p-type contact layer 226a are formed in a region other than the region 228 where dislocations are concentrated on the n-type GaN substrate 221a. Since the region 228 where dislocations are concentrated is not formed in the pn junction region between the n-type cladding layer 223a and the p-type cladding layer 225a formed through the light emitting layer 224a, Similar to the reference embodiment, the operation of the nitride-based semiconductor laser device can be easily stabilized, and from the region 228 where dislocations are concentrated. It is possible to reduce unnecessary emission.

  47 and 48 are cross-sectional views for explaining the manufacturing process for the nitride-based semiconductor laser device according to the tenth reference embodiment shown in FIG. A manufacturing process for the nitride-based semiconductor laser device according to the tenth reference embodiment is now described with reference to FIGS.

  First, as shown in FIG. 47, the process up to the p-side pad electrode 261 is formed and the back surface of the n-type GaN substrate 221a is polished using the same manufacturing process as in the first reference embodiment shown in FIGS. To do. Thereafter, the n-side electrode 232 is formed on the back surface of the n-type GaN substrate 221a by using a vacuum deposition method so as to be in contact with the entire back surface of the n-type GaN substrate 221a.

  Next, as shown in FIG. 48, the boundary region between adjacent elements is irradiated with the third harmonic (355 nm) of a YAG laser (fundamental wavelength: 1.06 μm), so that the surface of the p-side pad electrode 261 is exposed. The region 228 where dislocations are concentrated to a predetermined depth of the n-type GaN substrate 221a including the insulating film 260, the p-type cladding layer 225a, the light emitting layer 224a, the n-type cladding layer 223a and the n-type layer 222a is partially formed. Remove. As irradiation conditions at this time, the pulse frequency is set to about 10 kHz and the scanning speed is set to about 0.75 mm / sec. Thus, a groove 263 having a width W3 (for example, about 100 μm) larger than the width of the region 228 where dislocations are concentrated is formed in the region 228 where dislocations are concentrated. Thereafter, the element is separated into chips along the groove 263. In this manner, the nitride semiconductor laser element according to the tenth embodiment shown in FIG. 46 is formed.

  In the manufacturing process of the tenth reference embodiment, as described above, by using the YAG laser to form the groove portion 263 for separating the element into each chip, the width W3 of the groove portion 263 is a region 228 where dislocations are concentrated. Therefore, the region 228 where dislocations are concentrated can be easily removed. Thus, in addition to the step of forming the groove 263 for separating the element into each chip, it is not necessary to increase the number of steps for removing the region 228 where dislocations are concentrated. As a result, the manufacturing process can be simplified.

(11th reference form)
FIG. 49 is a cross-sectional view showing the structure of a nitride-based semiconductor laser device (semiconductor device) according to the eleventh reference embodiment of the present invention. Referring to FIG. 49, in the eleventh reference embodiment, unlike the ninth reference embodiment, the thickness of region 228 where the dislocations of n-type GaN substrate 221b are concentrated is the same as the concentration of dislocations of n-type GaN substrate 221b. The n-type GaN substrate 221b is removed from the upper surface to a predetermined depth so as to be smaller than the thickness of the region other than the region 228. Then, an n-type layer 222b, an n-type cladding layer 223b, a light emitting layer 224, a p-type cladding layer 225, and a p-type contact layer 226 are sequentially formed in a region other than the region 228 where dislocations are concentrated on the n-type GaN substrate 221b. Is formed. The n-type GaN substrate 221b, the n-type layer 222b, and the n-type cladding layer 223b have the same thickness and composition as the n-type GaN substrate 221, the n-type layer 222, and the n-type cladding layer 223 of the ninth reference embodiment, respectively. Have Here, the flat portions of the light emitting layer 224 and the p-type cladding layer 225 have a width (about 4.5 μm) smaller than the width of the n-type cladding layer 223b.

  The remaining configuration of the eleventh reference embodiment is the same as that of the ninth reference embodiment.

  In the eleventh reference embodiment, the configuration as described above is the same as in the ninth reference embodiment, in which the occurrence of leakage current due to the current flowing in the region 228 where dislocations are concentrated can be suppressed. The effect of can be obtained.

  FIG. 50 is a cross-sectional view for explaining the manufacturing process for the nitride-based semiconductor laser device according to the eleventh reference embodiment shown in FIG. Next, with reference to FIGS. 49 and 50, a manufacturing process for the nitride-based semiconductor laser device according to the eleventh embodiment will be described.

  First, up to the n-side electrode 232 is formed using the same manufacturing process as in the ninth reference embodiment shown in FIGS.

  Next, as shown in FIG. 50, an n-type GaN substrate 221b including an insulating film 230 is formed from the surface of the p-side pad electrode 231 in the boundary region between the nitride-based semiconductor laser element and the adjacent element by dicing. The regions 228 where dislocations are concentrated up to a predetermined depth in the n-type cladding layer 223b and the n-type layer 222b are partially removed. Thus, a groove portion 273 having a width W4 (for example, about 60 μm) larger than the width of the region 228 where dislocations are concentrated is formed in the region 228 where dislocations are concentrated in the element. Thereafter, the element is separated into chips along the groove 273. Thus, the nitride-based semiconductor laser device according to the eleventh reference embodiment shown in FIG. 49 is formed.

  In the manufacturing process of the eleventh reference embodiment, as described above, the groove portion 273 for separating the element into each chip is formed using dicing, so that the width W4 of the groove portion 273 is reduced in the region 228 where dislocations are concentrated. Since the width can be larger than the width, the region 228 where dislocations are concentrated can be easily removed as in the manufacturing process of the tenth embodiment. As a result, the manufacturing process can be simplified.

(Second Embodiment)
FIG. 51 is a cross-sectional view showing the structure of a nitride-based semiconductor laser device (semiconductor device) according to the second embodiment of the invention. Referring to FIG. 51, in the second embodiment, unlike the ninth to eleventh reference embodiments, a selective growth mask is formed in a region inside the region where dislocations are concentrated on the n-type GaN substrate. The case where it does is demonstrated.

  In the nitride-based semiconductor laser device according to the second embodiment, as shown in FIG. 51, the n-type GaN substrate 281 extends from the back surface to the front surface in the vicinity of the end portion of the n-type GaN substrate 281 and has a thickness of about 10 μm. A region 288 having dislocations having a width is formed in a stripe shape (elongated shape) with a period of about 400 μm. The n-type GaN substrate 281 has the same thickness and composition as the n-type GaN substrate 221 of the ninth reference embodiment. The n-type GaN substrate 281 is an example of the “substrate” in the present invention.

  Here, in the second embodiment, as shown in FIG. 52, in the region inside the region 288 where dislocations are concentrated on the n-type GaN substrate 281, a stripe shape made of a SiN film having a thickness of about 200 nm. A (long and narrow) selective growth mask 293 is formed. This selective growth mask 293 has a width W5 (about 3 μm) smaller than the width of the region 288 where dislocations are concentrated. The interval W6 from the element end to the end of the selective growth mask 293 is about 30 μm. The selective growth mask 293 is an example of the “first selective growth mask” in the present invention.

  As shown in FIG. 51, the region other than the region where the selective growth mask 293 is formed on the n-type GaN substrate 281 includes an n-type layer 282, an n-type cladding layer 283, a light emitting layer 284, a p-type cladding layer 285, and A p-type contact layer 286 is sequentially formed. The p-type cladding layer 285 has a convex portion, and the p-type contact layer 286 is formed on a region other than the flat portion of the p-type cladding layer 285. A ridge portion 287 is constituted by the convex portion of the p-type cladding layer 285 positioned inside the selective growth mask 293 and the p-type contact layer 286 formed on the convex portion of the p-type cladding layer 285. The Further, the dislocation of the n-type GaN substrate 281 propagates to the n-type layer 282, the n-type cladding layer 283, the light emitting layer 284, the p-type cladding layer 285, and the p-type contact layer 286 located outside the selective growth mask 293. Thus, a region 288 where dislocations are concentrated is formed. Note that the n-type layer 282, the n-type cladding layer 283, the light emitting layer 284, the p-type cladding layer 285, and the p-type contact layer 286 are the n-type layer 222, the n-type cladding layer 223, and the light emitting layer of the ninth reference embodiment, respectively. The layer 224, the p-type cladding layer 225, and the p-type contact layer 226 have the same thickness and composition. The n-type layer 282, the n-type cladding layer 283, the light emitting layer 284, the p-type cladding layer 285, and the p-type contact layer 286 are examples of the “semiconductor element layer” in the present invention.

  Here, in the second embodiment, the nitride-based semiconductor layers (282 to 286) located in the region inside the region 288 where dislocations are concentrated on the n-type GaN substrate 281 and the n-type GaN substrate 281 A recess 294 is formed between the nitride-based semiconductor layers (282 to 286) located in the region 288 where the dislocations are concentrated.

  A p-side ohmic electrode 289 is formed on the p-type contact layer 286 constituting the ridge portion 287. An insulating film 290 is formed so as to cover a region other than the upper surface of the p-side ohmic electrode 289. A p-side pad electrode 291 is formed on the surface of the insulating film 290 located inside the recess 294 so as to be in contact with the upper surface of the p-side ohmic electrode 289. The p-side ohmic electrode 289, the insulating film 290, and the p-side pad electrode 291 have the same thickness and composition as the p-side ohmic electrode 229, the insulating film 230, and the p-side pad electrode 231 of the ninth reference embodiment, respectively. . The p-side ohmic electrode 289 is an example of the “surface-side electrode” in the present invention.

  Further, an n-side electrode 292 is formed on the back surface of the n-type GaN substrate 281 so as to be in contact with a region other than the region 288 where dislocations are concentrated on the back surface of the n-type GaN substrate 281. The n-side electrode 292 has the same thickness and composition as the n-side electrode 232 of the ninth reference embodiment.

  In the second embodiment, as described above, the selective growth mask 293 is formed in the region inside the region 288 where dislocations are concentrated on the n-type GaN substrate 281, thereby forming the n-type GaN substrate 281 on the n-type GaN substrate 281. When the nitride semiconductor layers (282 to 286) are grown, since the nitride semiconductor layers (282 to 286) are not grown on the selective growth mask 293, dislocations on the n-type GaN substrate 281 are concentrated. Each nitride-based semiconductor layer (282 to 286) formed in a region inside the region 288, and each nitride-based semiconductor layer (282 in the region 288 where dislocations are concentrated on the n-type GaN substrate 281) ˜286) can be formed with recesses 294. Therefore, each nitride-based semiconductor layer (282 to 286) in which dislocation-concentrated regions 288 are formed and each nitride-based semiconductor layer (282 to 286) in which dislocation-concentrated regions 288 are not formed. Can be divided by the recess 294. As a result, by forming the p-side ohmic electrode 289 on the p-type contact layer 286 located on the inner side of the selective growth mask 293, the leakage current caused by the current flowing in the region 288 where dislocations are concentrated can be reduced. Occurrence can be suppressed. As a result, the light output during constant current driving of the element can be stabilized, so that the operation of the nitride-based semiconductor laser element can be stabilized. In addition, each nitride-based semiconductor layer (282 to 286) in which dislocation-concentrated regions 288 are formed, and each nitride-based semiconductor layer (282 to 286) in which dislocation-concentrated regions 288 are not formed Are divided by the recesses 294, so that light generated in the light-emitting layer 284 located in a region inside the region 288 where dislocations are concentrated is prevented from being absorbed in the region 288 where dislocations are concentrated. be able to. Accordingly, light absorbed in the region 288 where dislocations are concentrated can be prevented from being emitted again at an unintended wavelength, so that deterioration of color purity due to such re-emission can be suppressed. it can.

  52 to 55 are a plan view and a cross-sectional view 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 according to the second embodiment is now described with reference to FIGS.

  First, as shown in FIGS. 52 and 53, an n-type GaN substrate 281 is formed using a manufacturing process similar to that of the first reference embodiment shown in FIGS. A stripe-shaped (elongated) selective growth mask 293 made of a SiN film having a thickness of about 200 nm is formed in a predetermined region on the n-type GaN substrate 281. Specifically, the selective growth mask 293 having a width W5 of about 3 μm is provided on the n-type GaN substrate 281 with a gap W7 (W6 × 2) of about 60 μm so as to sandwich a region 288 where dislocations are concentrated. Form.

  Next, as shown in FIG. 54, an n-type layer 282, an n-type clad layer 283, a light emitting layer 284, and a p-type clad are formed on the n-type GaN substrate 281 on which the selective growth mask 293 is formed by using the MOCVD method. Layer 285 and p-type contact layer 286 are sequentially formed.

  At this time, in the second embodiment, since the nitride-based semiconductor layers (282 to 286) are not formed on the selective growth mask 293, the inner side of the region 288 where dislocations are concentrated on the n-type GaN substrate 281. Between the nitride-based semiconductor layers (282 to 286) formed in the region and the nitride-based semiconductor layers (282 to 286) formed in the region 288 where dislocations are concentrated on the n-type GaN substrate 281. A recess 294 is formed. In addition, the dislocations of the n-type GaN substrate 281 propagate to the nitride-based semiconductor layers (282 to 286) formed in the region 288 where dislocations are concentrated on the n-type GaN substrate 281, thereby causing the n-type GaN substrate 281 to propagate. A region 288 where dislocations are concentrated extending from the back surface of the substrate 281 to the top surface of the p-type contact layer 286 is formed.

  Next, as shown in FIG. 55, using the same manufacturing process as that of the first reference embodiment shown in FIGS. 289 is formed, and a ridge portion 287 composed of the convex portion of the p-type cladding layer 285 and the p-type contact layer 286 is formed. Further, after forming the insulating film 290 so as to cover the region other than the upper surface of the p-side ohmic electrode 289, the upper surface of the p-side ohmic electrode 289 is contacted on the surface of the insulating film 290 located inside the recess 294. Thus, the p-side pad electrode 291 is formed. Thereafter, the back surface of the n-type GaN substrate 281 is polished.

  Finally, as shown in FIG. 51, a metal layer (not shown) constituting the n-side electrode 292 is formed on the entire back surface of the n-type GaN substrate 281 using a vacuum deposition method, and then dislocations are formed. The nitride-based semiconductor laser device according to the second embodiment is formed by removing the metal layer located in the concentrated region 288.

  In the manufacturing process of the second embodiment, as described above, a width smaller than the width of the region 288 where dislocations are concentrated in the region inside the region 288 where dislocations are concentrated on the n-type GaN substrate 281. By forming the selective growth mask 293 having W5, the total amount of the source gas reaching the entire surface of the selective growth mask 293 is reduced, and accordingly, the position of the source growth gas 293 is positioned in the vicinity of the selective growth mask 293. As a result, the amount of source gas and its decomposition products that diffuse into the surface of each growing nitride semiconductor layer (282 to 286) is reduced. As a result, an increase in the amount of the source gas and its decomposition product supplied to the surface of each growing nitride-based semiconductor layer (282 to 286) located in the vicinity of the selective growth mask 293 can be reduced. It is possible to prevent the nitride-based semiconductor layers (282 to 286) located in the vicinity of the substrate from increasing in thickness. As a result, the thickness of each nitride-based semiconductor layer (282 to 286) can be prevented from becoming nonuniform between a position near the selective growth mask 293 and a position far from the selective growth mask 293.

( 12th reference form)
FIG. 56 is a cross-sectional view showing the structure of a nitride-based semiconductor laser device (semiconductor device) according to the twelfth embodiment of the present invention. Referring to FIG. 56, in the twelfth reference embodiment, unlike the second embodiment, dislocation-concentrated regions 288 and dislocation-concentrated regions 288 on the n-type GaN substrate 281 are provided. In the region, selective growth masks 313a and 313b made of an SiN film having a thickness of about 100 nm are formed. The selective growth mask 313a has a width W8 (about 188 μm) larger than the width of the region 288 where dislocations are concentrated. The selective growth mask 313b has a width W9 (about 2 μm) smaller than the width of the region 288 where dislocations are concentrated. The selective growth mask 313b is disposed with a gap W10 of about 5 μm from the selective growth mask 313a. The interval W11 between the selective growth masks 313b is about 10 μm. The selective growth mask 313a is an example of the “second selective growth mask” in the present invention, and the selective growth mask 313b is an example of the “first selective growth mask” in the present invention.

  The n-type layer 282a, the n-type clad layer 283a, the light emitting layer 284a, the p-type clad layer 285a, and the p-type contact are formed in regions other than the region where the selective growth masks 313a and 313b are formed on the n-type GaN substrate 281. Layers 286a are sequentially formed. The p-type cladding layer 285a has a convex portion, and the p-type contact layer 286a is formed on a region other than the flat portion of the p-type cladding layer 285a. A ridge portion 287a is constituted by the convex portion of the p-type cladding layer 285a located inside the selective growth mask 313b and the p-type contact layer 286a formed on the convex portion of the p-type cladding layer 285a. The The flat portions of the light emitting layer 284a and the p-type cladding layer 285a have a width (about 10.5 μm) smaller than the width of the n-type cladding layer 285a.

Here, in the twelfth reference embodiment, the region 288 where dislocations are concentrated is not formed in each nitride-based semiconductor layer (282a to 286a) formed on the n-type GaN substrate 281. In addition, each nitride-based semiconductor layer (282a to 286a) located on the n-type GaN substrate 281 on the region 288 side where dislocations are concentrated, and each nitride-based semiconductor layer located in the center on the n-type GaN substrate 281 A recess 314 is formed between (282a to 286a).

  A p-side ohmic electrode 289a is formed on the p-type contact layer 286a constituting the ridge portion 287a. An insulating film 310 is formed so as to cover a region other than the upper surface of the p-side ohmic electrode 289a. A p-side pad electrode 311 is formed in a predetermined region on the surface of the insulating film 310 so as to be in contact with the upper surface of the p-side ohmic electrode 289a. One end of the p-side pad electrode 311 is disposed on the insulating film 310 located on the region 288 where dislocations are concentrated, and the other end is a flat portion of the p-type cladding layer 285a. It is disposed on the insulating film 310 located above. Note that the n-type GaN substrate 281, the n-type layer 282a, the n-type clad layer 283a, the light emitting layer 284a, the p-type clad layer 285a, the p-type contact layer 286a, and the p-side ohmic electrode 289a are each of the ninth reference embodiment. The n-type GaN substrate 221, the n-type layer 222, the n-type cladding layer 223, the light emitting layer 224, the p-type cladding layer 225, the p-type contact layer 226, and the p-side ohmic electrode 229 have the same thickness and composition. The insulating film 310 and the p-side pad electrode 311 have the same thickness and composition as the insulating film 230 and the p-side pad electrode 231 of the ninth reference embodiment, respectively.

  Further, on the back surface of the n-type GaN substrate 281, similarly to the second embodiment, the n-side electrode 292 is in contact with a region other than the region 288 where dislocations are concentrated on the back surface of the n-type GaN substrate 281. Is formed.

In the twelfth reference embodiment, as described above, by forming the selective growth mask 313a in the region 288 where dislocations are concentrated on the n-type GaN substrate 281, each nitride semiconductor layer on the n-type GaN substrate 281 is formed. When growing (282a to 286a), since the nitride-based semiconductor layers (282a to 286a) do not grow on the selective growth mask 313a, dislocations are concentrated in the nitride-based semiconductor layers (282a to 286a). The formation of the region 288 can be suppressed. Thus, the occurrence of leakage current due to the current flowing through the region 288 where dislocations are concentrated can be suppressed. As a result, the light output during constant current driving of the element can be stabilized, so that the operation of the nitride-based semiconductor laser element can be stabilized. In addition, since current flowing in the region 288 where dislocations are concentrated can be reduced, unnecessary light emission from the region 288 where dislocations are concentrated can be reduced.

57 to 60 are a plan view and a cross-sectional view for explaining a manufacturing process of the nitride-based semiconductor laser device according to the twelfth embodiment shown in FIG. Next, with reference to FIGS. 56 to 60, a manufacturing process of the nitride semiconductor laser element according to the twelfth embodiment will be described.

  First, as shown in FIGS. 57 and 58, an n-type GaN substrate 281 is formed using a manufacturing process similar to that of the first reference embodiment shown in FIGS. Striped (elongated) selective growth masks 313a and 313b made of a SiN film having a thickness of about 100 nm are formed in a predetermined region on the n-type GaN substrate 281. Specifically, a selective growth mask 313a having a width W12 (W8 × 2) of about 376 μm is formed in a region 288 where dislocations are concentrated on the n-type GaN substrate 281. Also, a selective growth mask 313b having a width W9 of about 2 μm is formed on the n-type GaN substrate 281 with a gap W10 of about 5 μm from the selective growth mask 313a. The interval W11 between the selective growth masks 313b is about 10 μm.

  Next, as shown in FIG. 59, an n-type layer 282a, an n-type clad layer 283a, a light-emitting layer 284a, and a p-type layer are formed on the n-type GaN substrate 281 on which the selective growth masks 313a and 313b are formed using the MOCVD method. A mold cladding layer 285a and a p-type contact layer 286a are sequentially formed.

At this time, in the twelfth reference embodiment, the nitride semiconductor layers (282a to 286a) are not formed on the selective growth masks 313a and 313b. For this reason, the region 288 where dislocations are concentrated is not formed in each nitride-based semiconductor layer (282a to 286a). Further, each nitride-based semiconductor layer (282a to 286a) formed on the n-type GaN substrate 281 on the side of the region 288 where dislocations are concentrated, and a nitride-based layer formed in the central portion on the n-type GaN substrate 281. A recess 314 is formed between the semiconductor layers (282a to 286a).

  Next, as shown in FIG. 60, the p-side ohmic electrode is formed on the p-type contact layer 286 a located inside the recess 314 using the same manufacturing process as that of the first reference embodiment shown in FIGS. 8 to 11. In addition to forming 289a, a ridge portion 287a constituted by the convex portion of the p-type cladding layer 285a and the p-type contact layer 286a is formed. In addition, after forming the insulating film 310 so as to cover a region other than the upper surface of the p-side ohmic electrode 289a, the p-side ohmic electrode 289a is contacted with the upper surface of the p-side ohmic electrode 289a in a predetermined region on the surface of the insulating film 310. A side pad electrode 311 is formed. Thereafter, the back surface of the n-type GaN substrate 281 is polished.

Finally, as shown in FIG. 56, after a metal layer (not shown) constituting the n-side electrode 292 is formed on the entire back surface of the n-type GaN substrate 281 by using a vacuum evaporation method, By removing the metal layer located in the concentrated region 288, the nitride-based semiconductor laser device according to the twelfth embodiment is formed.

In the manufacturing process of the twelfth reference embodiment, as described above, a width smaller than the width of the region 288 where dislocations are concentrated in the region inside the region 288 where dislocations are concentrated on the n-type GaN substrate 281. By forming the selective growth mask 313b having W9, when the nitride-based semiconductor layers (282a to 286a) are grown, the total amount of source gas reaching the entire surface of the selective growth mask 313b is reduced. The amount of source gas and its decomposition products that are surface diffused from the surface of the selective growth mask 313b to the surface of each growing nitride semiconductor layer (282a to 286a) located in the vicinity of the selective growth mask 313b is reduced. As a result, an increase in the amount of source gas supplied to the surface of each of the growing nitride-based semiconductor layers (282a to 286a) located in the vicinity of the selective growth 313b and its decomposition products can be reduced, so that the selective growth mask 313b An increase in the thickness of each nitride-based semiconductor layer (282a to 286a) located in the vicinity can be suppressed. As a result, the thickness of each nitride-based semiconductor layer (282a to 286a) can be prevented from becoming nonuniform between a position near the selective growth mask 313b and a position far from the selective growth mask 313b.

FIG. 61 is a plan view for explaining the manufacturing process for the nitride-based semiconductor laser device according to the modification of the twelfth reference embodiment. Next, with reference to FIG. 61, a manufacturing process of the nitride semiconductor laser element according to the modification of the twelfth reference embodiment will be described.

In the manufacturing process of the nitride-based semiconductor laser device according to the modification of the twelfth reference embodiment, as shown in FIG. 61, the width of a region (not shown) where dislocations are concentrated on the n-type GaN substrate 281 is obtained. A selective growth mask 323b having a smaller width W13 (about 3 μm) is formed so as to surround the element formation region 281b. At this time, a plurality of openings 323c (element formation regions 281b) are arranged at a predetermined pitch along the element isolation direction (A direction in FIG. 61) and are adjacent to the cleavage direction (B direction in FIG. 61). The selective growth mask 323b is formed so that the portions 323c (element formation regions 281b) are alternately arranged. The width W14 in the B direction of the opening 323c (element formation region 281b) is set to about 12 μm. Further, the selective growth mask 323a is formed in the entire region separated from the selective growth mask 323b by an interval W15 of about 8 μm.

Thereafter, similar to the manufacturing process of the twelfth embodiment, after forming each nitride-based semiconductor layer (not shown), an insulating film (not shown) and each electrode layer (not shown) are formed.

In the manufacturing process of the nitride-based semiconductor laser device according to the modification of the twelfth reference embodiment, as described above, the n-type GaN substrate 281 has the plurality of openings 323c, and the openings 323c are along the A direction. After forming the selective growth mask 323b that is arranged at a predetermined pitch and the openings 323c adjacent to each other in the B direction are alternately arranged, the region other than the region where the selective growth mask 323b of the n-type GaN substrate 281 is formed is formed. By forming each nitride-based semiconductor layer on the region, the nitride-based semiconductor layers are not formed on the selective growth mask 323b. Therefore, each nitride-based semiconductor layer corresponds to the opening 323c on the n-type GaN substrate 281. It is formed only in the area to be. Thereby, the distance in the A direction of each nitride-based semiconductor layer formed on the region corresponding to the opening 323c of the n-type GaN substrate 281 is the nitride-based semiconductor continuously on the n-type GaN substrate 281 in the A direction. Since the distance is smaller than the distance in the A direction of each nitride-based semiconductor layer when each layer is formed, the occurrence of cracks can be suppressed as the distance in the A direction becomes smaller. In this case, since the openings 323c (element formation regions 281b) adjacent to each other in the B direction are alternately arranged, the element formation regions 281b can be alternately adjacent to each other in the A direction. As a result, it is possible to obtain an element formation region equivalent to the case where each nitride-based semiconductor layer is continuously formed in the A direction on the n-type GaN substrate 281 while preventing the occurrence of cracks. While preventing, it can suppress that the utilization efficiency of the n-type GaN board | substrate 281 falls.

( 13th reference form)
Figure 62 is a thirteenth plan view showing a structure of a nitride-based semiconductor laser device according to another embodiment of the present invention. 63 is a cross-sectional view taken along line 500-500 in FIG. FIG. 64 is a cross-sectional view showing details of the light emitting layer of the nitride-based semiconductor laser device according to the thirteenth embodiment shown in FIGS. 62 and 63. Referring to FIGS. 62-64, this thirteenth reference embodiment, unlike the ninth to twelfth reference embodiment and the second implementation embodiment, to remove the area where concentrated to dislocations to the n-type cladding layer At the same time, the case where the nitride semiconductor laser element is mounted inside the semiconductor laser will be described.

In the nitride-based semiconductor laser device 330 according to the thirteenth embodiment, as shown in FIG. 63, n-type GaN having a thickness of about 100 μm and doped with oxygen having a carrier concentration of about 5 × 10 ¹⁸ cm ^−3. An n-type layer 332 made of n-type GaN doped with Si and having a thickness of about 100 nm and a doping amount of about 5 × 10 ¹⁸ cm ⁻³ is formed on the substrate 331. The n-type GaN substrate 331 has a wurtzite type structure and a (0001) plane surface. Further, in the vicinity of both end portions of the n-type GaN substrate 331 and the n-type layer 332, concentration of dislocations extending from the back surface of the n-type GaN substrate 331 to the upper surface of the n-type layer 332 and having a width of about 10 μm, respectively. The region 331a is formed in a stripe shape (elongated shape). The n-type GaN substrate 331 is an example of the “substrate” in the present invention, and the n-type layer 332 is an example of the “semiconductor element layer” and the “first semiconductor layer” in the present invention.

Here, in the thirteenth embodiment, the n-type layer 332 has an n-type having a width D1 (about 7.5 μm) smaller than the width of the n-type GaN substrate 331 on a region other than the region 331a where dislocations are concentrated. A cladding layer 333, a light emitting layer 334, and a p-type cladding layer 335 are sequentially formed.

n-type cladding layer 333 has a thickness of about 400 nm, n-type Al 0 doped with Si having a carrier concentration of about 5 × 10 18 cm -3 doping amount and about 5 × 10 18 cm -3. It consists of 05 Ga 0.95 N. The n-type cladding layer 333 is an example of the “semiconductor element layer” and “first semiconductor layer” in the present invention.

As shown in FIG. 64, the light emitting layer 334 includes an n-type carrier block layer 334a, an n-type light guide layer 334b, an MQW active layer 334e, an undoped light guide layer 334f, and a p-type cap layer 334g. It is constituted by. n-type carrier blocking layer 334a has a thickness of about 5 nm, n-type Al ₀ doped with Si having a carrier concentration of about 5 × ¹⁰ 18 ^{cm -3} doping amount and about 5 × ¹⁰ 18 ^{cm -3} _0.1 Ga _0.9 N. n-type optical guide layer 334b has a thickness of about 100 nm, from n-type GaN doped with Si having a carrier concentration of about 5 × ¹⁰ 18 ^{cm -3} doping amount and about 5 × ¹⁰ 18 ^{cm -3} Become. The MQW active layer 334e includes four barrier layers 334c made of undoped In _0.05 Ga _0.95 N having a thickness of about 20 nm, and undoped In _0.15 Ga _0.85 N having a thickness of about 3 nm. The three well layers 334d made of are stacked alternately. The light emitting layer 334 is an example of the “semiconductor element layer” in the present invention, and the MQW active layer 334e is an example of the “active layer” in the present invention. The undoped light guide layer 334f is made of undoped GaN having a thickness of about 100 nm. The p-type cap layer 334g has a thickness of about 20 nm and is doped with Mg having a doping amount of about 4 × 10 ¹⁹ cm ⁻³ and a carrier concentration of about 5 × 10 ¹⁷ cm ⁻³ _{. It} consists of ₁ Ga _0.9 N.

As shown in FIG. 63, the p-type cladding layer 335 includes a p-type Al ₀ doped with Mg having a doping amount of about 4 × 10 ¹⁹ cm ⁻³ and a carrier concentration of about 5 × 10 ¹⁷ cm ^−3. _0.05 Ga _0.95 N. The p-type cladding layer 335 includes a flat portion 335a and a convex portion 335b formed so as to protrude upward from the center of the flat portion 335a. The flat portion 335a of the p-type cladding layer 335 is smaller than the width of the n-type GaN substrate 331 and has the same width D1 (about 7.5 μm) as the width of the light emitting layer 334, and is about 100 nm. It has a thickness. The convex portion 335b of the p-type cladding layer 335 has a width W16 (about 1.5 μm) smaller than the width of the light emitting layer 334, and has a protruding height of about 300 nm from the upper surface of the flat portion 335a. . The p-type cladding layer 335 is an example of the “semiconductor element layer” and “second semiconductor layer” in the present invention.

On the convex portion 335b of the p-type cladding layer 335, Mg having a thickness of about 10 nm, a doping amount of about 4 × 10 ¹⁹ cm ⁻³ and a carrier concentration of about 5 × 10 ¹⁷ cm ⁻³ is doped. A p-type contact layer 336 made of p-type GaN is formed. The projecting portion 335b of the p-type cladding layer 335 and the p-type contact layer 336 constitute a stripe-shaped (elongated) ridge portion 337 serving as a current path region. Further, on the p-type contact layer 336 constituting the ridge portion 337, a Pt layer having a thickness of about 5 nm, a Pd layer having a thickness of about 100 nm, and a thickness of about 150 nm are formed from the lower layer to the upper layer. A p-side ohmic electrode 338 composed of the Au layer is formed. The p-type cladding layer 335 and the p-type contact layer 336 are examples of the “semiconductor element layer” and the “second semiconductor layer” of the present invention, and the p-side ohmic electrode 338 is the “surface-side electrode” of the present invention. It is an example. Further, an insulating film 339 made of a SiN film having a thickness of about 250 nm is formed so as to cover a region other than the upper surface of the p-side ohmic electrode 338.

Here, in the thirteenth embodiment, as shown in FIG. 62 and FIG. 63, the predetermined area of the insulating film 339 is in contact with the upper surface of the p-side ohmic electrode 338 rather than the width of the n-type GaN substrate 331. A p-side pad electrode 341 having a small width B1 (about 150 μm) is formed. As shown in FIG. 62, the p-side pad electrode 341 is formed in a square shape when seen in a plan view. Then, one end portion 341a of the p-side pad electrode 341 extends to a region beyond the region where the one end portion 334h of the light emitting layer 334 is located, and the insulating film 339 located on the upper surface of the n-type layer 332 Formed on top. In addition, the other end portion 341b of the p-side pad electrode 341 is an insulating film located on the side surface of the n-type cladding layer 333 so as to extend to a region beyond the region where the other end portion 334i of the light emitting layer 334 is located. 339. One end 341a of the p-side pad electrode 341 is formed to have a flat surface that can be wire-bonded, while the other end 341b of the p-side pad electrode 341 is a flat surface that can be wire-bonded. Is not provided. For this reason, the distance between the other end 341b of the p-side pad electrode 341 and the ridge 337 is smaller than that of the one end 341a. The p-side pad electrode 341 includes a Ti layer having a thickness of about 100 nm, a Pd layer having a thickness of about 100 nm, and an Au layer having a thickness of about 3 μm from the lower layer to the upper layer. . A wire 342 for electrically connecting the one end 341a of the p-side pad electrode 341 and the outside is bonded on the one end 341a of the p-side pad electrode 341.

  In addition, an Al layer having a thickness of about 10 nm and a thickness of about 20 nm are formed on a region other than the region 331a where dislocations are concentrated on the back surface of the n-type GaN substrate 331, in order from the back surface of the n-type GaN substrate 331. An n-side electrode 343 is formed which is composed of a Pt layer having a thickness of 1 mm and an Au layer having a thickness of about 300 nm.

FIG. 65 is a perspective view showing the structure of a semiconductor laser using the nitride-based semiconductor laser device according to the thirteenth embodiment shown in FIGS. 62 and 63. Next, with reference to FIGS. 62, 63, and 65, the structure of the semiconductor laser using the nitride-based semiconductor laser device according to the thirteenth embodiment will be described.

As shown in FIG. 65, the semiconductor laser using the nitride-based semiconductor laser device 330 according to the thirteenth embodiment has a stem 351 on which the nitride-based semiconductor laser device 330 is mounted, a cap 352 for hermetically sealing, It has. The stem 351 is provided with three leads 351a to 351c, and among the three leads 351a to 351c, the leads 351a and 351b protrude from the upper surface of the stem 351. A block 353 is provided on the upper surface of the stem 351, and a submount 354 is provided on the side surface of the block 353. The nitride semiconductor laser element 330 according to the thirteenth reference embodiment is mounted on the submount 354. Specifically, the cleavage surface of the nitride-based semiconductor laser element 330 is arranged in parallel to the upper surface of the stem 351 so that the laser light is emitted in a direction perpendicular to the upper surface of the stem 351. Further, the wire 342 bonded to the end 341a (see FIGS. 62 and 63) of the p-side pad electrode 341 constituting the nitride semiconductor laser element 330 is electrically connected to the lead 351a. A light receiving element 355 is attached to a region on the upper surface of the stem 351 that faces the cleavage surface of the nitride semiconductor laser element 330. One end of a wire 356 is bonded to the light receiving element 355, and the other end of the wire 356 is bonded to a lead 351b. The cap 352 is welded onto the upper surface of the stem 351 so as to cover the nitride semiconductor laser element 330 and the light receiving element 355.

In the thirteenth embodiment, as described above, the width D1 (about 7.5 μm) of the light emitting layer 334 formed on the n-type cladding layer 333 is made smaller than the width of the n-type GaN substrate 331, and the light emitting layer 334 is formed. By making the width of the p-type cladding layer 335 formed above the same as the width of the light-emitting layer 334, a pn junction region between the n-type cladding layer 333 and the p-type cladding layer 335 formed via the light-emitting layer 334 Therefore, the pn junction capacitance can be reduced. Further, by reducing the width B1 (about 150 μm) of the p-side pad electrode 341 formed on the predetermined region of the insulating film 339 to be smaller than the width of the n-type GaN substrate 331, the p-side pad electrode 341 and the insulating film The parasitic capacitance formed by 339 and the n-type layer 332 can also be reduced. As a result, the response speed of the nitride-based semiconductor laser device 330 can be increased.

In the thirteenth embodiment, the end 341a of the p-side pad electrode 341 is positioned on the upper surface of the n-type layer 332 so as to extend to a region beyond the region where the one end 334h of the light emitting layer 334 is located. Even if the width B1 (about 150 μm) of the p-side pad electrode 341 is made smaller than the width of the n-type GaN substrate 331, the one end portion 334h of the light emitting layer 334 is located. One end portion 341a of the p-side pad electrode 341 beyond the region can be electrically connected to the lead 351a. Thereby, even when the width B1 (about 150 μm) of the p-side pad electrode 341 is made smaller than the width of the n-type GaN substrate 331, the connection between the p-side pad electrode 341 and the lead 351a does not become difficult. Further, by providing a flat portion 335 a on the p-type cladding layer 335 formed on the light-emitting layer 334, the p-type cladding layer 335 has a convex portion having a width W16 (about 1.5 μm) smaller than the width of the light-emitting layer 334. Even if 335b is provided, it is possible to suppress the lateral confinement of light from being excessively strong by the flat portion 335a, so that the transverse mode can be stabilized. Thereby, it is possible to prevent the light emission characteristics of the nitride-based semiconductor laser device 330 from deteriorating.

In the thirteenth embodiment, the n-type cladding layer 333, the light-emitting layer 334, and the p-type cladding layer 335 are formed on a region other than the region 331a where the dislocations of the n-type layer 332 are concentrated, thereby forming an n-type layer. Since the dislocation-concentrated region 331a is not formed in the clad layer 333, the light-emitting layer 334, and the p-type clad layer 335, current can be prevented from flowing through the dislocation-concentrated region 331a. Thereby, generation | occurrence | production of the leakage current resulting from an electric current flowing into the area | region 331a where the dislocation is concentrated can be suppressed. In addition, since current flowing in the region 331a where dislocations are concentrated can be suppressed, unnecessary light emission from the region 331a where dislocations are concentrated can be reduced. As a result, the operation of the nitride-based semiconductor laser device 330 can be stabilized.

  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 thirteenth reference embodiments and the first and second embodiments, examples in which the present invention is applied to nitride semiconductor laser elements and light-emitting diode elements have been described as examples of semiconductor elements. The present invention is not limited to this, and the present invention can also be applied to other semiconductor elements other than nitride semiconductor laser elements and light emitting diode elements.

In the first to thirteenth reference embodiments and the first and second embodiments, an n-type GaN substrate or a sapphire substrate including a nitride-based semiconductor layer is used as the substrate. However, the present invention is not limited to this. Instead, a substrate such as a spinel substrate, a Si substrate, a SiC substrate, a GaAs substrate, a GaP substrate, an InP substrate, a quartz substrate, or a ZrB ₂ substrate may be used.

Further, the first to thirteenth reference embodiment and the first, in the second embodiment, has been to form a nitride-based semiconductor layers of a wurtzite type structure, the present invention is not limited to this, sphalerite Each layer of a nitride-based semiconductor having a structure may be formed.

In the first to thirteenth reference embodiments and the first and second embodiments, each nitride semiconductor layer is crystal-grown using the MOCVD method. However, the present invention is not limited to this, and the HVPE method is used. And nitride-based semiconductors using a gas source MBE method (Molecular Beam Epitaxy) using TMAl, TMGa, TMIn, NH ₃ , SiH ₄ , GeH _4, Cp ₂ Mg, or the like as a source gas. Each layer may be crystal-grown.

In the first to thirteenth reference embodiments and the first and second embodiments, the nitride-based semiconductor layers are stacked so that the surface of each layer is a (0001) plane. However, the present invention is not limited to this, and nitrides are used. You may laminate | stack so that the surface of each type | system | group semiconductor layer may be another direction. For example, the nitride semiconductor layers may be stacked such that the surface of each layer is a (H, K, -HK, 0) plane such as a (1-100) plane or a (11-20) plane. In this case, since no piezoelectric field is generated in the MQW active layer, it is possible to suppress a decrease in the recombination probability between holes and electrons due to the inclination of the energy band of the well layer. As a result, the light emission efficiency of the MQW active layer can be improved. A substrate inclined from the (1-100) plane or the (11-20) plane may be used.

In the first to thirteenth reference embodiments and the first and second embodiments, the active layer having the MQW structure is used as the active layer. However, the present invention is not limited to this, and has a large quantum effect. The same effect can be obtained even with a single layer having a thickness or an active layer having a single quantum well structure.

In the first to thirteenth reference embodiments and the first and second embodiments, the substrate in which dislocations are concentrated is formed in a stripe shape. However, the present invention is not limited to this. A substrate in which dislocation-concentrated regions are formed in a shape other than stripes may be used. For example, in FIG. 4, instead of the mask 24, a substrate in which openings are scattered in a triangular lattice shape may be used to form a substrate in which dislocation-concentrated regions are scattered in a triangular lattice shape. . In this case, the same effect can be obtained by forming scattered insulating films and scattered high resistance regions corresponding to the regions where scattered dislocations are concentrated. Further, the same effect can be obtained by forming a recess so as to surround a region where scattered dislocations are concentrated.

In the first to eighth and tenth to thirteenth reference embodiments and the first and second embodiments, an n-type GaN substrate is formed by growing an n-type GaN layer on the sapphire substrate. However, the present invention is not limited to this, and an n-type GaN substrate may be formed by growing an n-type GaN layer on a GaAs substrate. Specifically, an n-type GaN layer doped with oxygen having a thickness of about 120 μm to about 400 μm is formed on the GaAs substrate by using the HVPE method, and then the n-type GaN substrate is removed by removing the GaAs substrate. Form. At this time, the carrier concentration by the Hall effect measurement of the n-type GaN substrate is about 5 × 10 ¹⁸ cm ⁻³ , and the impurity concentration by SIMS (Secondary Ion Mass Spectroscopy) is about 1 × 10 8. ^It is preferable to form so as to be ¹⁹ cm ⁻³ . Further, the n-type GaN layer may be grown in the lateral direction by forming a selective growth mask layer in a predetermined region on the GaAs substrate.

In the first, second, fourth, sixth to thirteenth reference embodiments and the first and second embodiments, a ridge portion is formed at a substantially central portion between regions where dislocations are concentrated. However, the present invention is not limited to this, and the ridge portion may be formed at a position of about 150 μm from one end and about 250 μm from the other end. In this case, the nitride-based semiconductor located in the region shifted from the central portion between the regions where dislocations are concentrated is more than the nitride-based semiconductor located near the center between the regions where dislocations are concentrated. Since the crystallinity is good, the lifetime of the nitride-based semiconductor laser device can be improved.

  In the third and fifth reference embodiments, the ohmic transparent electrode is formed on the n side. However, the present invention is not limited to this, and the ohmic transparent electrode may be formed on the p side.

It is sectional drawing which showed the structure of the nitride type semiconductor laser element (semiconductor element) by the 1st reference form of this invention. FIG. 2 is an enlarged cross-sectional view showing details of a light emitting layer of the nitride-based semiconductor laser device according to the first embodiment shown in FIG. 1. It is sectional drawing for demonstrating the manufacturing process of the nitride type semiconductor laser element by the 1st reference form shown in FIG. It is sectional drawing for demonstrating the manufacturing process of the nitride type semiconductor laser element by the 1st reference form shown in FIG. It is sectional drawing for demonstrating the manufacturing process of the nitride type semiconductor laser element by the 1st reference form shown in FIG. It is sectional drawing for demonstrating the manufacturing process of the nitride type semiconductor laser element by the 1st reference form shown in FIG. It is sectional drawing for demonstrating the manufacturing process of the nitride type semiconductor laser element by the 1st reference form shown in FIG. It is sectional drawing for demonstrating the manufacturing process of the nitride type semiconductor laser element by the 1st reference form shown in FIG. It is sectional drawing for demonstrating the manufacturing process of the nitride type semiconductor laser element by the 1st reference form shown in FIG. It is sectional drawing for demonstrating the manufacturing process of the nitride type semiconductor laser element by the 1st reference form shown in FIG. It is sectional drawing for demonstrating the manufacturing process of the nitride type semiconductor laser element by the 1st reference form shown in FIG. It is sectional drawing for demonstrating the manufacturing process of the nitride type semiconductor laser element by the 1st reference form shown in FIG. It is sectional drawing which showed the structure of the nitride type semiconductor laser element (semiconductor element) by the 2nd reference form of this invention. It is sectional drawing for demonstrating the manufacturing process of the nitride type semiconductor laser element by the 2nd reference form shown in FIG. It is sectional drawing for demonstrating the manufacturing process of the nitride type semiconductor laser element by the 2nd reference form shown in FIG. It is sectional drawing which showed the structure of the light emitting diode element (semiconductor element) by the 3rd reference form of this invention. FIG. 17 is an enlarged cross-sectional view illustrating details of a light emitting layer of the light emitting diode device according to the third embodiment shown in FIG. 16. FIG. 17 is a cross-sectional view for explaining a manufacturing process of the light-emitting diode element according to the third reference embodiment shown in FIG. 16. FIG. 17 is a cross-sectional view for explaining a manufacturing process of the light-emitting diode element according to the third reference embodiment shown in FIG. 16. FIG. 17 is a cross-sectional view for explaining a manufacturing process of the light-emitting diode element according to the third reference embodiment shown in FIG. 16. FIG. 17 is a cross-sectional view for explaining a manufacturing process of the light-emitting diode element according to the third reference embodiment shown in FIG. 16. It is sectional drawing which showed the structure of the nitride type semiconductor laser element (semiconductor element) by the 4th reference form of this invention. FIG. 23 is a cross-sectional view for illustrating the manufacturing process for the nitride-based semiconductor laser device according to the fourth reference embodiment shown in FIG. FIG. 23 is a cross-sectional view for illustrating the manufacturing process for the nitride-based semiconductor laser device according to the fourth reference embodiment shown in FIG. FIG. 23 is a cross-sectional view for illustrating the manufacturing process for the nitride-based semiconductor laser device according to the fourth reference embodiment shown in FIG. FIG. 23 is a cross-sectional view for illustrating the manufacturing process for the nitride-based semiconductor laser device according to the fourth reference embodiment shown in FIG. It is sectional drawing which showed the structure of the light emitting diode element (semiconductor element) by the 5th reference form of this invention. It is sectional drawing for demonstrating the manufacturing process of the light emitting diode element by the 5th reference form shown in FIG. It is sectional drawing which showed the structure of the nitride type semiconductor laser element (semiconductor element) by the 6th reference form of this invention. 1 is a cross-sectional view showing the structure of a nitride-based semiconductor laser device (semiconductor device) according to a first embodiment of the present invention. FIG. 31 is a cross-sectional view showing a structure of a nitride-based semiconductor laser device according to a first modification of the first embodiment shown in FIG. 30. FIG. 31 is a cross-sectional view showing a structure of a nitride-based semiconductor laser device according to a second modification of the first embodiment shown in FIG. 30. It is sectional drawing which showed the structure of the nitride type semiconductor laser element (semiconductor element) by the 7th reference form of this invention. It is sectional drawing which showed the structure of the nitride type semiconductor laser element (semiconductor element) by the 8th reference form of this invention. FIG. 35 is a cross-sectional view for illustrating the manufacturing process for the nitride-based semiconductor laser device according to the eighth reference embodiment shown in FIG. 34. FIG. 35 is a cross-sectional view for illustrating the manufacturing process for the nitride-based semiconductor laser device according to the eighth reference embodiment shown in FIG. 34. FIG. 35 is a cross-sectional view for illustrating the manufacturing process for the nitride-based semiconductor laser device according to the eighth reference embodiment shown in FIG. 34. FIG. 35 is a cross-sectional view for illustrating the manufacturing process for the nitride-based semiconductor laser device according to the eighth reference embodiment shown in FIG. 34. It is sectional drawing which showed the structure of the nitride type semiconductor laser element (semiconductor element) by the 9th reference form of this invention. FIG. 40 is a cross-sectional view for explaining a manufacturing process for the nitride-based semiconductor laser device according to the ninth reference embodiment shown in FIG. 39. FIG. 40 is a cross-sectional view for explaining a manufacturing process for the nitride-based semiconductor laser device according to the ninth reference embodiment shown in FIG. 39. FIG. 40 is a cross-sectional view for explaining a manufacturing process for the nitride-based semiconductor laser device according to the ninth reference embodiment shown in FIG. 39. FIG. 40 is a cross-sectional view for explaining a manufacturing process for the nitride-based semiconductor laser device according to the ninth reference embodiment shown in FIG. 39. FIG. 40 is a cross-sectional view for explaining a manufacturing process for the nitride-based semiconductor laser device according to the ninth reference embodiment shown in FIG. 39. FIG. 40 is a cross-sectional view for explaining a manufacturing process for the nitride-based semiconductor laser device according to the ninth reference embodiment shown in FIG. 39. It is sectional drawing which showed the structure of the nitride type semiconductor laser element (semiconductor element) by the 10th reference form of this invention. FIG. 47 is a cross sectional view for illustrating the manufacturing process for the nitride-based semiconductor laser device according to the tenth reference embodiment shown in FIG. 46. FIG. 47 is a cross sectional view for illustrating the manufacturing process for the nitride-based semiconductor laser device according to the tenth reference embodiment shown in FIG. 46. It is sectional drawing which showed the structure of the nitride type semiconductor laser element (semiconductor element) by the 11th reference form of this invention. FIG. 50 is a cross sectional view for illustrating the manufacturing process for the nitride-based semiconductor laser device according to the eleventh reference embodiment shown in FIG. 49. It is sectional drawing which showed the structure of the nitride type semiconductor laser element (semiconductor element) by 2nd Embodiment of this invention. FIG. 52 is a plan view and a cross-sectional view for explaining a manufacturing process for the nitride-based semiconductor laser device according to the second embodiment shown in FIG. 51. FIG. 52 is a plan view and a cross-sectional view for explaining a manufacturing process for the nitride-based semiconductor laser device according to the second embodiment shown in FIG. 51. FIG. 52 is a plan view and a cross-sectional view for explaining a manufacturing process for the nitride-based semiconductor laser device according to the second embodiment shown in FIG. 51. FIG. 52 is a plan view and a cross-sectional view for explaining a manufacturing process for the nitride-based semiconductor laser device according to the second embodiment shown in FIG. 51. It is sectional drawing which showed the structure of the nitride type semiconductor laser element (semiconductor element) by the 12th reference form of this invention. FIG. 57 is a plan view and a cross-sectional view for illustrating the manufacturing process for the nitride-based semiconductor laser device according to the twelfth embodiment shown in FIG. 56. FIG. 57 is a plan view and a cross-sectional view for illustrating the manufacturing process for the nitride-based semiconductor laser device according to the twelfth embodiment shown in FIG. 56. FIG. 57 is a plan view and a cross-sectional view for illustrating the manufacturing process for the nitride-based semiconductor laser device according to the twelfth embodiment shown in FIG. 56. FIG. 57 is a plan view and a cross-sectional view for illustrating the manufacturing process for the nitride-based semiconductor laser device according to the twelfth embodiment shown in FIG. 56. It is a top view for demonstrating the manufacturing process of the nitride type semiconductor laser element by the modification of 12th reference form. It is the top view which showed the structure of the nitride type semiconductor laser element by the 13th reference form of this invention. FIG. 63 is a cross-sectional view taken along line 500-500 in FIG. 62. FIG. 66 is a cross-sectional view showing details of the light emitting layer of the nitride-based semiconductor laser device according to the thirteenth embodiment shown in FIGS. 62 and 63; FIG. 66 is a perspective view showing the structure of a semiconductor laser using the nitride-based semiconductor laser device according to the thirteenth reference embodiment shown in FIGS. 62 and 63.

Explanation of symbols

1 n-type GaN substrate (substrate, nitride semiconductor substrate)
2, 202 n-type layer (semiconductor element layer)
3, 52, 203 n-type cladding layer (semiconductor element layer)
4, 53, 204, 224, 224a, 284, 284a, 334 Light emitting layer (semiconductor element layer)
5, 54, 205 p-type cladding layer (semiconductor element layer)
6, 55, 206 p-type contact layer (semiconductor element layer)
8, 56, 208, 228, 288, 331a Dislocation concentrated region 9, 58, 79, 149, 179, 209, 229, 229a, 289, 289a, 338 p-side ohmic electrode (surface side electrode)
12, 57, 100 Insulating film 13, 33 n-side electrode (back side electrode)
60, 110 n-side ohmic transparent electrode (back side electrode)
80 n-type current blocking layer (semiconductor element layer)
120, 190 Ion implantation layer (high resistance region)
130, 160 Recess 201 Substrate (nitride semiconductor substrate)
212 n-side electrode (surface-side electrode)
221, 221a, 221b, 281, 331 n-type GaN substrate (substrate)
222, 222a, 222b, 282, 282a, 332 n-type layer (semiconductor element layer, first semiconductor layer)
223, 223a, 223b, 283, 283a, 333 n-type cladding layer (semiconductor element layer, first semiconductor layer)
225, 225a, 285, 285a, 335 p-type cladding layer (semiconductor element layer, second semiconductor layer)
226, 226a, 286, 286a, 336 p-type contact layer (semiconductor element layer, second semiconductor layer)
293, 313b, 323b selective growth mask (first selective growth mask)
313a, 323a selective growth mask (second selective growth mask)

Claims (9)

A substrate having a back surface region where dislocations are concentrated on at least a part of the back surface;
A semiconductor element layer formed on the surface of the substrate and having a surface region where the dislocations are concentrated on at least a part of the surface;
A recess formed in a region inside the surface region where the dislocations are concentrated;
A surface-side electrode formed so as to be in contact with a region of the surface of the semiconductor element layer other than the surface region where the dislocation is concentrated;
A backside electrode formed so as to be in contact with a region of the back surface of the substrate other than the back surface region where the dislocation is concentrated.   The semiconductor element according to claim 1, further comprising an insulating film formed on the back surface region where the dislocations are concentrated.   The semiconductor device according to claim 1, wherein the substrate includes a nitride-based semiconductor substrate.   The semiconductor element according to claim 1, wherein the surface electrode is formed in a region inside the recess. 5. The semiconductor device according to claim 1, further comprising an insulating film formed on the surface region where the dislocations are concentrated and in the recess . On the surface of the substrate having a back surface region where dislocations are concentrated on at least a part of the back surface, the surface has a surface region where the dislocations are concentrated on at least a part of the surface, and the surface where the dislocations are concentrated Forming a semiconductor element layer having a recess formed in a region inside the region;
Forming a surface-side electrode so as to be in contact with a region of the surface of the semiconductor element layer other than the surface region where the dislocation is concentrated;
Forming a back side electrode so as to be in contact with a region of the back surface of the substrate other than the back surface region where the dislocation is concentrated.   The method for manufacturing a semiconductor element according to claim 6, further comprising a step of forming an insulating film on the back surface region where the dislocations are concentrated.   The method of manufacturing a semiconductor element according to claim 6, wherein the step of forming the surface side electrode includes a step of forming the surface side electrode in a region inside the recess. The method for manufacturing a semiconductor element according to claim 6, further comprising a step of forming an insulating film on the surface region where the dislocations are concentrated and in the recess .

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