Claims
- 1. A method of producing a semiconductor device, comprising the steps of:
- forming exposed and unexposed areas on a gallium arsenide substrate by forming a refractory metal layer on a portion of the gallium arsenide substrate to form a Schottky junction between the refractory metal layer and the gallium arsenide substrate;
- oxidizing the refractory metal layer in a gas containing oxygen; and
- carrying out capless annealing of the gallium arsenide substrate having the oxidized refractory metal layer thereon in an atmosphere containing arsenic.
- 2. The method of claim 1, wherein the oxygen-containing gas is selected from the group consisting of O.sub.2 gas, O.sub.3 gas, a mixture of O.sub.2 gas and an inert gas, a mixture of O.sub.2 gas and N.sub.2 gas, a mixture of O.sub.3 gas and an inert gas and a mixture of O.sub.3 gas and N.sub.2 gas.
- 3. The method of claim 1, wherein the oxidizing step is carried out one of thermal oxidation and plasma oxidation.
- 4. The method of claim 1, wherein the oxidizing step forms an oxide film having a first thickness on an upper surface of the metal layer, a second thickness of said metal layer adjacent said gallium arsenide substrate remaining unoxidized.
- 5. The method of claim 4, wherein the first thickness is at least about 50 .ANG. and the second thickness is at least about 1000 .ANG..
- 6. The method of claim 4, wherein the first thickness is at least about 100 .ANG. and the second thickness is at least about 1000 .ANG..
- 7. The method of claim 1, wherein the metal layer is selected from the group consisting of nitrides, silicides and silicon nitrides of a high melting point metal.
- 8. The method of claim 7, wherein the refractory metal layer is tungsten nitride.
- 9. The method of claim 1, additionally comprising the step of patterning the metal layer before oxidizing.
- 10. The method of claim 1, additionally comprising the step of patterning the metal layer after oxidizing.
- 11. A method of producing a semiconductor device, comprising the steps of:
- forming exposed and unexposed areas on a gallium arsenide substrate by sputtering a refractory metal layer on a portion of the gallium arsenide substrate to form a Schottky junction between the refractory metal layer and the gallium arsenide substrate;
- thermally oxidizing the refractory metal layer in a gas containing oxygen; and
- carrying out capless annealing of the gallium arsenide substrate having the oxidized refractory metal layer thereon in an atmosphere containing arsenic.
- 12. The method of claim 11, wherein the oxygen-containing gas is selected from the group consisting of O.sub.2 gas, O.sub.3 gas, a mixture of O.sub.2 gas and an inert gas, a mixture of O.sub.2 gas and N.sub.2 gas, a mixture of O.sub.3 gas and an inert gas and a mixture of O.sub.3 gas and N.sub.2 gas.
- 13. The method of claim 11, wherein the oxidizing step forms an oxide film having a first thickness on an upper surface of the refractory metal layer, a second thickness of said refractory metal layer adjacent said gallium arsenide substrate remaining unoxidized.
- 14. The method of claim 13, wherein the first thickness is at least about 50 .ANG. and the second thickness is at least about 1000 .ANG..
- 15. The method of claim 13, wherein the first thickness is at least about 100 .ANG. and the second thickness is at least about 1000 .ANG..
- 16. The method of claim 11, wherein the refractory metal layer is selected from the group consisting of nitrides, silicides and silicon nitrides of a high melting point metal.
- 17. The method of claim 16, wherein the refractory metal layer is tungsten nitride.
- 18. The method of claim 11, additionally comprising the step of patterning the refractory metal layer before oxidizing.
- 19. The method of claim 11, additionally comprising the step of patterning the refractory metal layer after oxidizing.
- 20. A method of producing a semiconductor device, comprising the steps of:
- sputtering a refractory metal layer on a gallium arsenide substrate to form a Schottky junction therebetween;
- oxidizing by one of thermal oxidation and plasma oxidation the surface of the refractory metal layer to produce a structure comprising a layer of oxidized refractory metal layer overlying a layer of unoxidized refractory metal layer adjacent the gallium arsenide substrate; and
- carrying out capless annealing of the gallium arsenide substrate having the oxidized refractory metal layer thereon in an atmosphere containing arsenic.
- 21. The method of claim 20, wherein the oxygen-containing gas is selected from the group consisting of O.sub.2 gas, O.sub.3 gas, a mixture of O.sub.2 gas and an inert gas, a mixture of O.sub.2 gas and N.sub.2 gas, a mixture of O.sub.3 gas and an inert gas and a mixture of O.sub.3 gas and N.sub.2 gas.
- 22. The method of claim 20, wherein the oxidizing step forms an oxide film having a first thickness on an upper surface of the refractory metal layer, a second thickness of said refractory metal layer adjacent said gallium arsenide substrate remaining unoxidized.
- 23. The method of claim 22, wherein the first thickness is at least about 50 .ANG. and the second thickness is at least about 1000 .ANG..
- 24. The method of claim 22, wherein the first thickness is at least about 100 .ANG. and the second thickness is at least about 1000 .ANG..
- 25. The method of claim 20, wherein the refractory metal layer is selected from the group consisting of nitrides, silicides and silicon nitrides of a high melting point metal.
- 26. The method of claim 25, wherein the refractory metal layer is tungsten nitride.
- 27. The method of claim 20, additionally comprising the step of patterning the refractory metal layer before oxidizing.
- 28. The method of claim 11, additionally comprising the step of patterning the refractory metal layer after oxidizing.
- 29. A method of producing a semiconductor device, comprising the steps of:
- (a) forming a layer of refractory metal on a gallium arsenide substrate containing a first impurity doped region;
- (b) oxidizing the surface of the layer of refractory metal in a gas containing oxygen to produce a structure comprising an oxidized refractory metal layer overlying an unoxidized refractory metal layer that is adjacent the first impurity doped region;
- (c) patterning said refractory metal to produce a gate over said first impurity doped region;
- (d) producing second and third impurity doped regions on either side of and aligned with said gate; and
- (e) after said oxidizing step, carrying out capless annealing in an atmosphere containing arsenic to activate said first region to form a channel region, said second region to form a source region and said third region to form a drain region, wherein said oxidized layer prevents crystallization disorder in the channel region.
- 30. The method of claim 29, wherein the oxidized refractory metal layer is at least about 50 .ANG. and the unoxidized refractory metal layer is at least about 1000 .ANG..
- 31. The method of claim 29, wherein the oxidized refractory metal layer is at least about 100 .ANG. and the unoxidized refractory metal layer is at least about 1000 .ANG..
- 32. The method of claim 29, wherein the recited steps are in the order (a), (b), (c), (d) and then (e).
- 33. The method of claim 29, wherein the recited steps are in the order (a), (c), (b), (d) and then (e).
- 34. A method of producing a semiconductor device, comprising the steps of:
- forming a refractory metal layer on a gallium arsenide substrate to form a Schottky junction therebetween;
- oxidizing the refractory metal layer in a gas containing oxygen;
- patterning the refractory metal layer to produce an exposed surface of the gallium arsenide substrate; and
- carrying out capless annealing of the gallium arsenide substrate having the oxidized refractory metal layer thereon and the exposed surface in an atmosphere containing arsenic.
Priority Claims (2)
Number |
Date |
Country |
Kind |
63-1331 |
Jan 1988 |
JPX |
|
63-293564 |
Nov 1988 |
JPX |
|
Parent Case Info
This application is a continuation of application Ser. No. 07/294,648, filed Jan. 9, 1989 now abandoned.
US Referenced Citations (12)
Foreign Referenced Citations (6)
Number |
Date |
Country |
59-222965 |
Dec 1984 |
JPX |
60-189968 |
Sep 1985 |
JPX |
60-213065 |
Oct 1985 |
JPX |
61-187364 |
Aug 1986 |
JPX |
63-111666 |
May 1988 |
JPX |
63-173375 |
Jul 1988 |
JPX |
Non-Patent Literature Citations (1)
Entry |
Uchitomi et al., "Properties of WNX films deposited by reactive sputtering for self-aligned gate GaAs Mesfets," Workshop on Refractory Metals & Silicides for VLSI IV, May 1986. |
Continuations (1)
|
Number |
Date |
Country |
Parent |
294648 |
Jan 1989 |
|