AlInN film, two-dimensional photonic crystal resonator, method for manufacturing these, and semiconductor light-emitting element
Provided is a technique for manufacturing a semiconductor light-emitting element for which it is possible to dramatically increase light emission efficiency to a greater degree than in the past. An AlInN film provided on a GaN epitaxial film that is formed on a substrate, wherein: the AlInN film is formed by lamination of AlInN layers; between the laminated AlInN layers, there is provided a cap layer that comprises GaN, AlN, or AlGaN, and has a thickness of 0.1-10 nm; a super lattice structure is formed; the total thickness exceeds 200 nm; and the root-mean-square height RMS is 3 nm or less. A method for forming an AlInN film, the method being such that: a step for forming an AlInN layer is repeated a plurality of times, said step involving using any of an organometallic vapor phase growth method, a molecular beam epitaxy method, and a sputtering method to form the AlInN layer to a thickness of 200 nm or less by epitaxial growth in an atmosphere of 700-850° C. on a GaN epitaxial film formed on a substrate; and the AlInN layer is grown until a prescribed thickness is reached.
1. An AlInN film provided on a GaN epitaxial film formed on a substrate, which is formed by stacking AlInN layers, wherein
a cap layer having a thickness of 0.1 to 10 nm and made of GaN, AlN or AlGaN is provided between the stacked AlInN layers to form a super-lattice structure,
the total thickness exceeds 200 nm, and
the root mean square height (RMS) is 3 nm or less.
2. The AlInN film according to claim 1 , wherein a thickness of each of the AlInN layers in the super-lattice structure is 200 nm or less.
3. The AlInN film according to claim 2 , wherein the number of In droplets on the surface of the AlInN layer is 5×10 6 pieces/cm 2 or less.
4. The AlInN film according to claim 2 , wherein the AlInN is AlxIn1−xN (x=0.75 to 0.90).
5. A method for manufacturing a two-dimensional photonic crystal resonator, which manufactures a two-dimensional photonic crystal resonator by using the AlInN film according to claim 2 as a sacrificial layer, comprising: forming the AlInN film and the light-emitting layer on a substrate where a GaN epitaxial film is formed, and then forming an air clad layer by wet-etching the AlInN film.
6. The AlInN film according to claim 1 , wherein the number of In droplets on the surface of the AlInN layer is 5×10 6 pieces/cm 2 or less.
7. The AlInN film according to claim 6 , wherein no In droplets exists on the surface of the AlInN layer.
8. The AlInN film according to claim 7 , wherein the AlInN is AlxIn1−xN (x=0.75 to 0.90).
9. The AlInN film according to claim 6 , wherein the AlInN is AlxIn1−xN (x=0.75 to 0.90).
10. A method for manufacturing a two-dimensional photonic crystal resonator, which manufactures a two-dimensional photonic crystal resonator by using the AlInN film according to claim 6 as a sacrificial layer, comprising: forming the AlInN film and the light-emitting layer on a substrate where a GaN epitaxial film is formed, and then forming an air clad layer by wet-etching the AlInN film.
11. The AlInN film according to claim 1 , wherein the AlInN is AlxIn1−xN (x=0.75 to 0.90).
12. A method for manufacturing a two-dimensional photonic crystal resonator, which manufactures a two-dimensional photonic crystal resonator by using the AlInN film according to claim 1 as a sacrificial layer, comprising: forming the AlInN film and the light-emitting layer on a substrate where a GaN epitaxial film is formed, and then forming an air clad layer by wet-etching the AlInN film.
13. The AlInN film according to claim 1 , wherein a thickness of the AlInN layer formed in one AlInN layer forming step is 75 to 100 nm.