Method for preparing Ge1-x-ySnxEy (E=P, As, Sb) semiconductors and related Si-Ge-Sn-E and Si-Ge-E analogs

• US 7,238,596 B2
• Filed: 06/14/2004
• Issued: 07/03/2007
• Est. Priority Date: 06/13/2003
• Status: Active Grant

• Current Assignee: Arizona Board of Regents (University of Arizona)
• Original Assignee: Arizona Board of Regents (University of Arizona)
• Inventors: Kouvetakis, John, Tolle, John, Bauer, Matthew, Cook, Candi
• Primary Examiner(s): Geyer; Scott B.
• Assistant Examiner(s): Patel; Reema
• Application Number:
  US10/559,980
• Publication Number:
  US 20060134895A1
• Time in Patent Office: 1,114 Days
• Field of Search: 438/565, 438/569, 438/508, 438/507, 438/511
• US Class Current: 438/507
• CPC Class Codes: C23C 16/22 characterised by the deposition of inorganic material, other than metallic material
• CPC Class Codes: C30B 25/02 Epitaxial-layer growth
• CPC Class Codes: C30B 29/08 Germanium
• CPC Class Codes: C30B 29/52 Alloys
• CPC Class Codes: H01L 21/2252 using predeposition of impurities into the semiconductor surface, e.g. from a gaseous phase

Abstract

A process for is provided for synthesizing a compound having the formula E(GeH₃)₃ wherein E is selected from the group consisting of arsenic (As), antimony (Sb) and phosphorus (P). GeH₃Br and [CH₃)₃Si]₃E are combined under conditions whereby E(GeH₃)₃ is obtained. The E(GeH₃)₃ is purified by trap-to-trap fractionation. Yields from about 70% to about 76% can be obtained. The E(GeH₃)₃ can be used as a gaseous precursor for doping a region of a semiconductor material comprising Ge, SnGe, SiGe and SiGeSn in a chemical vapor deposition reaction chamber.

Claims

1. A method for synthesizing a compound having the formula E(GeH₃)₃ wherein E is selected from the group consisting of arsenic (As), antimony (Sb) and phosphorus (P), the method comprising combining GeH₃Br with [(CH₃)₃Si]₃E under conditions whereby E(GeH₃)₃ is obtained.

2. The method of claim 1 further comprising purifying the obtained E(GeH₃)₃.

3. The method of claim 1 wherein the step of purifying the obtained E(GeH₃)₃ comprises trap-to-trap fractionation.

4. The method of claim 1 wherein E(GeH₃)₃ is obtained with a yield from about 70% to about 76%.

5. A method for synthesizing a compound having the formula E(GeH₃)₃ wherein E is selected from the group consisting of arsenic (As), antimony (Sb) and phosphorus (P), the method comprising combining GeH₃Br with [(CH₃)₃Si]₃E to obtain E(GeH₃)₃ according to the formula:

3 GeH₃Br+[(CH₃)₃Si)]₃E→

3(CH₃)₃SiBr+(GeH₃)3E

6. The method of claim 5 further comprising purifying the obtained E(GeH₃)₃.

7. The method of claim 5 wherein the step of purifying the obtained E(GeH₃)₃ comprises trap-to-trap fractionation.

8. The method of claim 5 wherein E(GeH₃)₃ is obtained with a yield from about 70% to about 76%.

9. A method for doping a region of a semiconductor material in a chemical vapor deposition reaction chamber, the method comprising introducing into the chamber a gaseous precursor having the formula E(GeH₃)₃, wherein E is selected from the group consisting of arsenic (As), antimony (Sb) and phosphorus (P).

10. The method of claim 9 wherein the semiconductor material comprises silicon (Si).

11. The method of claim 9 wherein the semiconductor material comprises germanium (Ge).

12. The method of claim 9 wherein the semiconductor material comprises SiGeSn.

13. The method of claim 9 wherein the semiconductor material comprises SnGe.

14. A method for depositing a doped epitaxial Ge—

Sn layer on a substrate in a chemical vapor deposition reaction chamber, the method comprising;

introducing into the chamber a gaseous precursor comprising SnD₄ mixed in H₂ under conditions whereby the epitaxial Ge—

Sn layer is formed on the substrate; and

introducing into the chamber a gaseous precursor having the formula E(GeH₃)₃, wherein E is selected from the group consisting of arsenic (As), antimony (Sb) and phosphorus (P).

15. The method of claim 14 wherein the gaseous precursor is introduced at a temperature in a range of about 250°

C. to about 350°

C.

16. The method of claim 14 wherein the substrate comprises silicon.

17. The method of claim 14 wherein the silicon comprises Si(100).

18. The method of claim 14 wherein the Ge—

Sn layer comprises Sn_xGe_1-x and x is in a range from about 0.02 to about 0.20.

19. A method for forming a Group IV semiconductor film, the method comprising

forming the Group IV semiconductor film by a chemical vapor deposition method, wherein the Group IV semiconductor film is doped with impurities comprising an element E at a concentration ranging from about 10²¹ atoms/cm³ to about several percent using a precursor having the formula E(GeH₃)₃ wherein E is selected from the group consisting of arsenic (As), phosporous (P) and antimony (Sb).

20. A method for forming a Group IV semiconductor film, the method comprising:

forming the Group IV semiconductor film by a chemical vapor deposition method; and

while forming the Group IV semiconductor film, doping the film with impurities comprising an element B at a concentration ranging from about 10²¹ atoms/cm³ to about 3 at. % using a precursor having the formula E(GeH₃)₃ wherein B is selected from the group consisting of arsenic (As), antimony (Sb) and phosphorus (P).

21. The method for forming a Group IV semiconductor film according to claim 20, wherein arsenic (As), antimony (Sb) and phosphorus (P) are added to the Group IV semiconductor film by diffusion methods.

22. The method for forming a Group IV semiconductor film according to claim 20, wherein the doping step comprises introducing into a reaction chamber the precursor having the formula E(GeH₃)₃ and a reactant comprising SnD₄, GeH₄ or Ge₂H₆.

23. A method of preparing (E)H_x (GeH₃)_3-x, where x=1 or 2 and E is selected from the group consisting of P, As, Sb, the method comprising reacting inorganic or organometallic compounds of the E element with an alkali germyl or a halogenated germane.

24. The method of preparing (E)H_x (GeH₃)_3-x according to claim 23 wherein the alkali germyl comprises KGeH₃.

25. The method of preparing (R)H_x (GeH₃)_3-x according to claim 23 wherein the halogenated germane comprises BrGeH₃.