Semiconductor laser, semiconductor device, and their manufacture methods

A semiconductor laser comprising:

• a substrate made of SiC;
• a plurality of AlxGa1−xN patterns (0≦x≦1) formed on a surface of said substrate and dispersively distributed in an in-plane of said substrate;
• an AlyGa1−yN buffer layer (0≦y≦1) covering the surface of said substrate and said AlxGa1−xN patterns;
• and
• a laser structure formed on said AlyGa1−yN buffer layer, wherein x of said AlxGa1−xN pattern and y of said AlyGa1−yN buffer layer satisfy a relation of y<x.

A semiconductor laser comprising:

• a substrate made of SiC;
• a plurality of AlxGa1−xN patterns (0≦x≦1) formed on a surface of said substrate and dispersively distributed in an in-plane of said substrate;
• an AlyGa1−yN buffer layer (0≦y≦1) covering the surface of said substrate and said AlxGa1−xN patterns;
• and
• a laser structure formed on said AlyGa1−yN buffer layer, wherein x of said AlxGa1−xN pattern satisfies an inequality 0.09≦x≦0.40.

A semiconductor laser comprising:

• a substrate made of SiC;
• a plurality of AlxGa1−xN patterns (0≦x≦1) formed on a surface of said substrate and dispersively distributed in an in-plane of said substrate;
• an AlyGa1−yN buffer layer (0≦y≦1) covering the surface of said substrate and said AlxGa1−xN patterns;
• and
• a laser structure formed on said AlyGa1−yN buffer layer, wherein as viewed along a direction normal to the surface of said substrate, an oscillation region of said laser structure is disposed so as not to be superposed upon said AlxGa1−xN pattern.

A semiconductor laser comprising:

• a substrate made of SiC;
• a plurality of AlxGa1−xN patterns (0≦x≦1) formed on a surface of said substrate and dispersively distributed in an in-plane of said substrate;
• an AlyGa1−yN buffer layer (0≦y≦1) covering the surface of said substrate and said AlxGa1−xN patterns;
• and
• a laser structure formed on said AlyGa1−yN buffer layer, wherein as viewed along a direction normal to the surface of said substrate, an oscillation region of said laser structure is completely included in said AlxGa1−xN pattern.

A nitride based group III-V compound semiconductor device, comprising:

• a semiconductor substrate;
• a lamination pattern formed on a partial surface of said semiconductor substrate, said lamination pattern including a lower-level layer made of nitride based group III-V compound semiconductor and a higher-level layer made of different material from the nitride based group III-V compound semiconductor;
• and
• a grown layer covering said lamination pattern, said grown layer being made of nitride based compound semiconductor easier to be grown on side walls of the lower-level layer than on a surface of the higher-level layer.

A semiconductor laser comprising:

• a semiconductor substrate;
• a buffer layer disposed on a partial surface of said semiconductor substrate, said buffer layer being made of group III-V compound semiconductor and including an eaves portion;
• and
• a laser structure formed on said buffer layer, an oscillation region of said laser structure being disposed so as to be superposed upon the eaves portion, as viewed along a direction normal to a surface of said semiconductor substrate.

A semiconductor laser comprising:

• a semiconductor substrate;
• an AlGaN pattern formed on a partial surface of said semiconductor substrate, said AlGaN pattern being made of AlxGa1−xN (0≦x≦1);
• a buffer layer made of AlyGa1−yN (0≦y≦1) and covering a surface of said AlGaN pattern and surfaces of said semiconductor substrate on both sides of said AlGaN pattern;
• a semiconductor layer covering a surface of said buffer layer and surfaces of said semiconductor substrate on both sides of said buffer layer;
• and
• a laser structure formed on said buffer layer, an oscillation region of said laser structure being disposed so as not to be superposed upon said AlGaN pattern as viewed along a direction normal to the surface of said semiconductor substrate.

A nitride based group III-V compound semiconductor device, comprising:

• a semiconductor substrate;
• a lamination pattern formed on a partial surface of said semiconductor substrate, said lamination pattern including a lower-level layer made of nitride based group III-V compound semiconductor and a higher-level layer made of different material from the nitride based group III-V compound semiconductor;
• and
• a buffer region made of nitride based compound semiconductor and covering a surface of said lamination pattern and surfaces of said semiconductor substrate on both sides of said lamination pattern, the nitride based compound semiconductor being easier to grow on side walls of the lower-level layer than on a surface of the higher-level layer.