Wide band-gap semiconductors having low bipolar resistivity and method of formation

• US 5,252,499 A
• Filed: 08/15/1988
• Issued: 10/12/1993
• Est. Priority Date: 08/15/1988
• Status: Expired due to Term

• Current Assignee: Rothschild G F Neumark
• Original Assignee: Rothschild G F Neumark
• Inventors: Rothschild, G. F. Neumark
• Primary Examiner(s): Kunemund, Robert
• Assistant Examiner(s): OJAN, OURMAZD
• Application Number:
  US07/232,405
• Time in Patent Office: 1,884 Days
• Field of Search: 437/937, 437/22, 437/24, 148/DIG. 69, 148/DIG. 84
• US Class Current: 438/475
• CPC Class Codes: H01L 21/02557 Sulfides
• CPC Class Codes: H01L 21/0256 Selenides
• CPC Class Codes: H01L 21/02562 Tellurides
• CPC Class Codes: H01L 21/02579 P-type
• CPC Class Codes: H01L 21/38 Diffusion of impurity materials, e.g. doping materials, electrode materials, into or out of a semiconductor body, or between semiconductor regions
• CPC Class Codes: H01L 33/0083 for devices with an active region comprising only II-VI compounds
• CPC Class Codes: H01L 33/285 characterised by the doping materials
• CPC Class Codes: Y10S 148/064 Gp II-VI compounds
• CPC Class Codes: Y10S 148/084 Ion implantation of compound devices
• CPC Class Codes: Y10S 438/919 Compensation doping

Abstract

A wide band-gap semiconductor, such as a II-VI semiconductor having low bipolar resistivity and a method for producing such a semiconductor. To form this semiconductor, atomic hydrogen is used to neutralize compensating contaminants. Alternatively, the semiconductor dopant and hydrogen are introduced into the undoped semiconductor together, and later, the hydrogen is removed leaving an acceptably compensation free wide band-gap semiconductor.

Claims

1. A method of forming a p-n junction from a wide band-gap semiconductor, comprising forming an n-type side and a p-type side of a semiconductor by doping the n-type side to form an n-type semiconductor and doping the p-type side to form a p-type semiconductor, then introducing at least a sufficient quantity of atomic hydrogen into at least one side of the doped semiconductor to neutralize a portion of the compensators of at least that side to reduce the resistivity of at least that side to yield a wide band-gap semiconductor having reduced resistivity on at least that side.

2. The method of preparing the p-n junction of claim 1, wherein atomic hydrogen is introduced into the n-type side of the semiconductor.

3. The method of forming the p-n junction of claim 1, wherein atomic hydrogen is introduced into the p-type side of the semiconductor.

4. The method of forming the p-n junction of claim 1, wherein atomic hydrogen is incorporated at a temperature of about 250°

C.

5. The method of forming the p-n junction of claim 1, wherein the p-type side is p-type ZnSe.

6. The method of forming the p-n junction of claim 1, wherein the semiconductor is a II-VI semiconductor.

7. The method of forming the p-n junction of claim 1, wherein atomic hydrogen is introduced by hydrogen plasma exposure.

8. The method of forming the p-n junction of claim 1, wherein atomic hydrogen is introduced by electro-chemical hydrogen insertion.

9. The method of forming the p-n junction of claim 1, wherein atomic hydrogen is introduced at a temperature below about 400°

C.

10. A method of forming a low resistivity semiconductor from a wide band-gap semiconductor substrate that has a tendency to become compensated when it is doped, comprising selectively doping the semiconductor substrate with an effective amount of dopant to induce acceptable conductivity, together with an effective amount of atomic hydrogen to act as a compensator and block unacceptably high occurrences of other compensators, then removing an effective amount of the added hydrogen to reduce the resistivity of the semiconductor, the hydrogen removed under conditions to limit other movement within the semiconductor.

11. The method of forming the low resistivity semiconductor of claim 10, wherein the semiconductor is a II-VI semiconductor.

12. The method of forming the low resistivity semiconductor of claim 10, wherein the hydrogen is removed by heating the semiconductor to an effective temperature for inducing hydrogen movement while the remainder of the semiconductor remains acceptably stable.

13. The method of forming the low resistivity semiconductor of claim 12, wherein the heating for the removal of hydrogen is carried out in vacuo.

14. The method of forming the low resistivity semiconductor of claim 10, wherein the hydrogen is removed by gettering.

15. The method of forming the low resistivity semiconductor of claim 10, wherein the hydrogen is removed by electric field induced hydrogen drift.

16. The method of forming the low resistivity semiconductor of claim 10, wherein the sample is heated in a non-hydrogen ambient, for removal of hydrogen.

17. The method of forming the low resistivity semiconductor of claim 13, wherein the semiconductor is heated to a temperature between about 100°

to 500°

C. for the removal of hydrogen.

18. The method of forming the low resistivity semiconductor of claim 13, wherein the semiconductor is heated to a temperature between about 150°

to 400°

C.

19. The method of forming the low resistivity semiconductor of claim 16, wherein the semiconductor is heated to a temperature between about 100°

to 500°

C. for the removal of hydrogen.

20. The method of forming the low resistivity semiconductor of claim 16, wherein the semiconductor is heated to a temperature between about 150°

to 400°

C.

21. The method of forming a low resistivity semiconductor of claim 16, wherein the semiconductor is selected from the group consisting of CdS, CdSe, CdTe, ZnO, ZnS, ZnSe, ZnTe.

22. A method of forming low resistivity semiconductor from a wide band-gap semiconductor substrate having unacceptably high resistivity due to excessive compensators, by introducing at least an effective quantity of atomic hydrogen into the semiconductor substrate to neutralize an acceptable portion of the compensators.