Methods for enhancing P-type doping in III-V semiconductor films
Methods of doping a semiconductor film are provided. The methods comprise epitaxially growing the III-V semiconductor film in the presence of a dopant, a surfactant capable of acting as an electron reservoir, and hydrogen, under conditions that promote the formation of a III-V semiconductor film doped with the p-type dopant. In some embodiments of the methods, the epitaxial growth of the doped III-V semiconductor film is initiated at a first hydrogen partial pressure which is increased to a second hydrogen partial pressure during the epitaxial growth process.
1. A method of doping a III-V semiconductor film, the method comprising:
presenting a p-type dopant which comprises cadmium to an epitaxial growth process;
presenting a surfactant capable of acting as an electron reservoir to the epitaxial growth process;
presenting hydrogen to the epitaxial growth process; and
growing a III-V semiconductor film under conditions including the p-type dopant, the surfactant, and the hydrogen throughout the epitaxial growth process that promote the formation of a p-type doped III-V semiconductor film.
2. The method recited in claim 1 , wherein the presenting a surfactant capable of acting as an electron reservoir to the epitaxial growth process comprises presenting Sb.
3. The method recited in claim 1 , wherein the presenting a surfactant capable of acting as an electron reservoir to the epitaxial growth process comprises presenting Bi.
4. The method recited in claim 1 , wherein the presenting hydrogen to the epitaxial growth process comprises:
initiating the epitaxial growth process at a first hydrogen partial pressure; and
increasing the hydrogen partial pressure from the first hydrogen partial pressure to a second hydrogen partial pressure during the epitaxial growth process.
5. The method recited in claim 1 , further including annealing the p-type doped III-V semiconductor film to remove co-doped hydrogen from the III-V semiconductor film.
6. The method recited in claim 1 , wherein growing the III-V semiconductor film includes using an OMVPE growth process.
7. The method recited in claim 1 , wherein growing the III-V semiconductor film includes using a MBE process.
8. The method recited in claim 1 , wherein growing the III-V semiconductor film includes using a CBE process.
9. The method of claim 1 , wherein the III-V semiconductor film is a GaP semiconductor film.
10. A method of doping a semiconductor film, comprising:
growing a semiconductor film in the presence of
a p-type dopant which comprises cadmium;
a surfactant; and
a hydrogen source; and
creating conditions during the growing of the semiconductor film that promote the formation of a semiconductor film doped with the p-type dopant, such that the p-type dopant, the surfactant and the hydrogen source are present throughout growth of the semiconductor film doped with the p-type dopant.
11. The method recited in claim 10 , wherein the surfactant is capable of acting as an electron reservoir.
12. The method recited in claim 11 , wherein the surfactant is Bi.
13. The method recited in claim 11 , wherein the surfactant is Sb.
14. The method recited in claim 13 , wherein growing a semiconductor film in the presence of a hydrogen source further includes:
initiating the growth of the semiconductor film at a first hydrogen partial pressure; and
increasing the hydrogen partial pressure from the first hydrogen partial pressure to a second hydrogen partial pressure during the growth of the semiconductor film.
15. The method of claim 10 , wherein the semiconductor film is a GaP semiconductor film.
16. A method of doping a III-V semiconductor film, the method comprising:
growing epitaxially the III-V semiconductor film entirely in the presence of a p-type dopant which is cadmium, a surfactant capable of acting as an electron reservoir, and hydrogen, under conditions that promote the formation of a p-type doped III-V semiconductor film.
17. The method recited in claim 16 , wherein the growing epitaxially of the III-V semiconductor film further includes:
initiating the epitaxial growth at a first hydrogen partial pressure and maintaining the first hydrogen partial pressure for a first period of time during the growing; and
increasing the hydrogen partial pressure to a second hydrogen partial pressure and maintaining the second hydrogen partial pressure for a second period of time during the growing.
18. The method of claim 16 , further including annealing the p-type doped III-V semiconductor film at a temperature and for a time sufficient to remove hydrogen from the p-type doped III-V semiconductor film.
19. The method of 16 , wherein the III-V semiconductor film is a GaP semiconductor film.