METHODS FOR ENHANCING P-TYPE DOPING IN III-V SEMICONDUCTOR FILMS

• US 20130203243A1
• Filed: 10/28/2011
• Published: 08/08/2013
• Est. Priority Date: 10/28/2010
• Status: Active Grant

• Current Assignee: University of Utah Research Foundation (State of Utah)
• Original Assignee: University of Utah (State of Utah)
• Inventors: Liu, Feng, Stringfellow, Gerald, Zhu, Junyi
• Granted Patent: US 9,721,810 B2
• Time in Patent Office: Days
• US Class Current: 438/478
• 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 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 that promote the formation of a p-type doped III-V semiconductor film.

2. The method recited in claim 1, wherein the presenting a p-type dopant to an epitaxial growth process comprises presenting magnesium.

3. The method recited in claim 1, wherein the presenting a p-type dopant to an epitaxial growth process comprises presenting beryllium.

4. The method recited in claim 1, wherein the presenting a p-type dopant to an epitaxial growth process comprises presenting cadmium.

5. 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.

6. 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.

7. The method recited in claim 1, wherein the presenting hydrogen to the epitaxial growth process comprises:

presenting hydrogen at a first hydrogen partial pressure; and

increasing the hydrogen partial pressure from the first hydrogen partial pressure to a second hydrogen partial pressure.

8. 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.

9. The method recited in claim 1, wherein growing a III-V semiconductor film includes using an OMVPE growth process.

10. The method recited in claim 1, wherein growing a III-V semiconductor film includes using a MBE process.

11. The method recited in claim 1, wherein growing a III-V semiconductor film includes using a CBE process.

12. A method of doping a semiconductor film, comprising:

growing a semiconductor film in the presence of

a dopant;

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.

13. The method recited in claim 12, wherein the dopant is selected from the group consisting of magnesium, beryllium and cadmium.

14. The method recited in claim 13, wherein the surfactant is capable of acting as an electron reservoir.

15. The method recited in claim 14, wherein the surfactant is Bi.

16. The method recited in claim 14, wherein the surfactant is Sb.

17. The method recited in claim 16, wherein growing a semiconductor film in the presence of a hydrogen source further includes:

presenting hydrogen at a first hydrogen partial pressure; and

changing the hydrogen partial pressure from the first hydrogen partial pressure to a second hydrogen partial pressure.

18. A method of doping a III-V semiconductor film, the method comprising:

growing epitaxially the III-V semiconductor film in the presence of a p-type dopant selected from the group consisting of magnesium, beryllium and 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.

19. The method recited in claim 18, wherein the growing epitaxially of the III-V semiconductor film further includes:

maintaining a first hydrogen partial pressure for a first period of time during the growing; and

maintaining a second hydrogen partial pressure for a second period of time during the growing.

20. The method of claim 18, 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.