Method for producing compound semiconductor light-emitting device
View Patent ↗It is intended to provide a production method that enables at least one of improvement in transparency, reduction in sheet resistance, homogenization in planar distribution of sheet resistance, and reduction in contact resistance related to a contact layer regarding a transparent conductive oxide film included in a compound semiconductor light-emitting device. A method for producing a compound semiconductor light-emitting device includes depositing on a substrate a compound semiconductor stacked-layer body including a light-emitting layer, depositing a transparent conductive oxide film on the compound semiconductor stacked-layer body, and annealing the transparent conductive oxide film and thereafter cooling the same in a vacuum atmosphere.
1. A method for producing a compound semiconductor light-emitting device, comprising:
depositing on a substrate a compound semiconductor stacked-layer body including a light-emitting layer;
depositing a transparent conductive oxide film on the compound semiconductor stacked-layer body;
subjecting the transparent conductive oxide film to first annealing in a gaseous atmosphere containing oxygen;
subjecting, after the first annealing, the transparent conductive oxide film to second annealing in a vacuum atmosphere or in a gaseous atmosphere free of oxygen; and
cooling, after the second annealing, the transparent conductive oxide film in a vacuum atmosphere.
2. The method according to claim 1 wherein pressure in the vacuum atmosphere during the annealing is 10 Pa or less.
3. The method according to claim 1 wherein the cooling in the vacuum atmosphere is continued to a temperature of 200° C. or less.
4. The method according to claim 1 wherein the transparent conductive oxide film is formed of an oxide including indium.
5. The method according to claim 4 wherein the transparent conductive oxide film is formed of ITO or IZO.
6. The method according to claim 1 wherein the transparent conductive oxide film has a thickness in a range of 100 nm to 400 nm.
7. The method according to claim 1 wherein the second annealing is carried out only in the gaseous atmosphere free of oxygen.
8. The method according to claim 7 wherein the second annealing is carried out in a nitrogen gas atmosphere, in an argon gas atmosphere, or in a mixed gas atmosphere of nitrogen gas and argon gas.
9. The method according to claim 1 wherein the second annealing is carried out only in the vacuum atmosphere.
10. A compound semiconductor light-emitting device produced by the following process steps:
depositing on a substrate a compound semiconductor stacked-layer body including a light-emitting layer;
depositing a transparent conductive oxide film on the compound semiconductor stacked-layer body;
subjecting the transparent conductive oxide film to first annealing in a gaseous atmosphere containing oxygen;
subjecting, after the first annealing, the transparent conductive oxide film to second annealing in a vacuum or in a gaseous atmosphere free of oxygen; and
cooling, after the second annealing, the transparent conductive in a vacuum atmosphere,
wherein a planar distribution of a sheet resistance of the transparent conductive oxide film is more homogenized than a planar distribution of a sheet resistance of a transparent conductive oxide film that is not cooled in the vacuum atmosphere.