Method of manufacturing a semiconductor light-emitting device
A semiconductor light-emitting device having a high light emission property and preventing an electrode from being peeled off during wire bonding. Also disclosed is a method of manufacturing a semiconductor light-emitting device 1 in which an n-type semiconductor layer ( 13 ), a light-emitting layer ( 14 ), and a p-type semiconductor layer ( 15 ) are formed on a substrate ( 11 ), a transparent positive electrode ( 16 ) is formed on the p-type semiconductor layer ( 15 ), a positive electrode bonding pad ( 17 ) is formed on the transparent positive electrode ( 16 ), and a negative electrode bonding pad ( 18 ) is formed on the n-type semiconductor layer ( 13 ).
1. A method of manufacturing a semiconductor light-emitting device in which an n-type semiconductor layer, a light-emitting layer, and a p-type semiconductor layer are formed on a substrate, a transparent positive electrode is formed on the p-type semiconductor layer, a positive electrode bonding pad is formed on the transparent positive electrode, and a negative electrode bonding pad is formed on the n-type semiconductor layer, the method comprising:
forming, on the p-type semiconductor layer, the transparent positive electrode made of a transparent conductive oxide material having an oxygen concentration that is lower than a stoichiometric composition;
performing an annealing process on the transparent positive electrode in an atmosphere including oxygen; and
performing a reannealing process on the transparent positive electrode in an oxygen-free atmosphere.
2. The method of manufacturing a semiconductor light-emitting device according to claim 1 ,
wherein the oxygen concentration is 0.01 at % to 10 at % lower than the stoichiometric composition.
3. The method of manufacturing a semiconductor light-emitting device according to claim 1 ,
wherein the semiconductor layer is composed of a gallium nitride compound semiconductor.
4. The method of manufacturing a semiconductor light-emitting device according to claim 1 ,
wherein the transmittance of the transparent positive electrode before the annealing process is in the range of 80% to 90%,
the transmittance of the transparent positive electrode is improved by the annealing process, and
the reannealing process is performed on the transparent positive electrode in the oxygen-free atmosphere.
5. The method of manufacturing a semiconductor light-emitting device according to claim 1 ,
wherein the sheet resistance of the transparent positive electrode is reduced by the reannealing process.
6. The method of manufacturing a semiconductor light-emitting device according to claim 1 ,
wherein the transparent positive electrode is formed on substantially the entire upper surface of the p-type semiconductor layer.
7. The method of manufacturing a semiconductor light-emitting device according to claim 1 ,
wherein the annealing process is performed at a temperature in the range of 250° C. to 600° C.
8. The method of manufacturing a semiconductor light-emitting device according to claim 1 ,
wherein the reannealing process is performed in a N 2 gas atmosphere at a temperature in the range of 200° C. to 500° C.
9. The method of manufacturing a semiconductor light-emitting device according to claim 1 ,
wherein the annealing process and the reannealing process are performed on the transparent positive electrode having an oxygen concentration that is lower than the stoichiometric composition to reduce the sheet resistance of the transparent positive electrode to 20 Ω/□ or less.
10. The method of manufacturing a semiconductor light-emitting device according to claim 1 ,
wherein the transparent conductive oxide material forming the transparent positive electrode is selected from at least one of ITO (In 2 O 3 —SnO 2 ), AZnO (ZnO—Al 2 O 3 ), IZnO (In 2 O 3 —ZnO), and GZO (ZnO—Ga 2 O 3 ).