Methods for enhancing P-type doping in III-V semiconductor films

• US 9,721,810 B2
• Filed: 10/28/2011
• Issued: 08/01/2017
• Est. Priority Date: 10/28/2010
• Status: Expired due to Fees

• Current Assignee: University of Utah Research Foundation (State of Utah)
• Original Assignee: University of Utah Research Foundation (State of Utah)
• Inventors: Stringfellow, Gerald, Zhu, Junyi, Liu, Feng
• Primary Examiner(s): Lee, Cheung
• Assistant Examiner(s): Smith, Stephen C
• Application Number:
  US13/322,403
• Publication Number:
  US 20130203243A1
• Time in Patent Office: 2,104 Days
• Field of Search: 136255, 438483
• CPC Class Codes: H01L 21/02538 Group 13/15 materials
• CPC Class Codes: H01L 21/02543 Phosphides
• CPC Class Codes: H01L 21/02579 P-type
• CPC Class Codes: H01L 21/02581 Transition metal or rare earth elements
• CPC Class Codes: H01L 21/0262 Reduction or decomposition of gaseous compounds, e.g. CVD
• CPC Class Codes: Y10S 117/913 Graphoepitaxy or surface modification to enhance epitaxy

Abstract

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.

Claims

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.