Method for wafer outgassing control
Embodiments disclosed herein generally relate to methods for controlling substrate outgassing such that hazardous gasses are eliminated from a surface of a substrate after a III-V epitaxial growth process or an etch clean process, and prior to additional processing. An oxygen containing gas is flowed to a substrate in a load lock chamber, and subsequently a non-reactive gas is flowed to the substrate in the load lock chamber. As such, hazardous gases and outgassing residuals are decreased and/or removed from the substrate such that further processing may be performed.
1. A method, comprising:
(a) depositing an epitaxial layer on a surface of a substrate in a chamber;
(b) removing the substrate having the epitaxial layer thereon from the chamber and delivering the substrate into a substrate access chamber;
(c) flowing an oxygen containing gas into the substrate access chamber at a first pressure;
(d) removing residuals of the epitaxial layer deposition from the epitaxial layer by reacting the oxygen containing gas with the residuals of the epitaxial layer deposited;
(e) ceasing the flow of the oxygen containing gas into the substrate access chamber;
(f) flowing a non-reactive gas into the substrate access chamber at a second pressure greater than the first pressure;
(g) ceasing the flow of the non-reactive gas into the substrate access chamber; and
(h) removing the non-reactive gas from the substrate access chamber.
2. The method of claim 1 , further comprising:
(i) repeating (f)-(h) for at least one additional cycle.
3. The method of claim 1 , wherein the non-reactive gas is a nitrogen-containing gas.
4. The method of claim 1 , wherein the oxygen containing gas is oxygen.
5. The method of claim 1 , wherein the first pressure is between about 60 Torr and about 220 Torr.
6. The method of claim 1 , wherein the second pressure is above about 200 Torr.
7. The method of claim 1 , wherein the removing of the non-reactive gas from the substrate access chamber is at a third pressure, wherein the third pressure is less than the first pressure.
8. The method of claim 7 , wherein the third pressure is less than about 1 Torr.
9. The method of claim 1 , wherein the flowing of the oxygen containing gas into the substrate access chamber occurs for between about 1 second and about 60 seconds.
10. The method of claim 1 , wherein the flowing of the non-reactive gas into the substrate access chamber occurs for between about 30 seconds and about 400 seconds.
11. The method of claim 1 , wherein the flowing of the oxygen containing gas into the substrate access chamber is via a conduit from the oxygen containing gas source to the substrate access chamber.
12. A method, comprising:
(a) depositing an epitaxial layer on a surface of a substrate in a chamber;
(b) removing the substrate having the epitaxial layer thereon from the chamber and delivering the substrate into a load lock chamber;
(c) flowing an oxygen containing gas into the load lock chamber at a first pressure, the first pressure is between about 60 Torr and about 220 Torr;
(d) removing residuals of the epitaxial layer deposition from the epitaxial layer by reacting the oxygen containing gas with the residuals of the epitaxial layer deposited;
(e) ceasing the flowing of the oxygen containing gas into the load lock chamber;
(f) flowing a nitrogen containing gas into the load lock chamber at a second pressure greater than the first pressure; and
(g) pumping the nitrogen containing gas out of the load lock chamber.
13. The method of claim 12 , further comprising:
(h) repeating (f)-(g) for at least one additional cycle.
14. The method of claim 12 , wherein the second pressure is above about 200 Torr.
15. The method of claim 12 , wherein the pumping of the nitrogen containing gas out of the load lock chamber is at a third pressure, wherein the third pressure is less than the first pressure.
16. The method of claim 12 , wherein the flowing of the oxygen containing gas into the load lock chamber occurs for between about 1 second and about 60 seconds, and the flowing of the nitrogen containing gas into the load lock chamber occurs for between about 30 seconds and about 400 seconds.
17. A method for controlling outgassing, comprising:
(a) depositing an epitaxial layer on a surface of a substrate in a chamber;
(b) removing the substrate having the epitaxial layer thereon from the chamber and delivering the substrate to a load lock chamber;
(c) flowing oxygen gas into the load lock chamber at a first pressure, wherein the first pressure is between about 60 Torr and about 220 Torr;
(d) removing residuals of the epitaxial layer deposition from the epitaxial layer by reacting the oxygen gas with the residuals of the epitaxial layer deposited;
(e) ceasing the flowing of the oxygen gas into the load lock chamber;
(f) flowing a non-reactive gas into the load lock chamber at a second pressure, wherein the second pressure is above about 200 Torr;
(g) pumping the non-reactive gas out of the load lock chamber at a third pressure, wherein the third pressure is below about 1 Torr; and
(h) repeating (f)-(g) for at least one additional cycle.