Removing metal contamination from surfaces of a processing chamber

Patent metadata

Field	Value
Publication number	US-11842888-B2
Application number	US-202218091550-A
Country	US
Kind code	B2
Filing date	Dec 30, 2022
Priority date	Oct 5, 2018
Publication date	Dec 12, 2023
Grant date	Dec 12, 2023

Abstract

A method for cleaning surfaces of a substrate processing chamber includes a) supplying a first gas selected from a group consisting of silicon tetrachloride (SiCl 4 ), carbon tetrachloride (CCl 4 ), a hydrocarbon (C x H y where x and y are integers) and molecular chlorine (Cl 2 ), boron trichloride (BCl 3 ), and thionyl chloride (SOCl 2 ); b) striking plasma in the substrate processing chamber to etch the surfaces of the substrate processing chamber; c) extinguishing the plasma and evacuating the substrate processing chamber; d) supplying a second gas including fluorine species; e) striking plasma in the substrate processing chamber to etch the surfaces of the substrate processing chamber; and f) extinguishing the plasma and evacuating the substrate processing chamber.

First claim

What is claimed is:

1. A method for cleaning surfaces of a substrate processing chamber, comprising:
a) supplying a first gas selected from a group consisting of silicon tetrachloride (SiCl 4 ), carbon tetrachloride (CCl 4 ), a hydrocarbon (C x H y where x and y are integers) and molecular chlorine (Cl 2 ), boron trichloride (BCl 3 ), and thionyl chloride (SOCl 2 ), wherein the first gas is configured to selectively etch tin (Sn) relative to silicon (Si);
b) striking plasma in the substrate processing chamber with the first gas to selectively etch Sn relative to Si from the surfaces of the substrate processing chamber;
c) extinguishing the plasma struck in b) and evacuating the substrate processing chamber;
d) supplying a second gas including fluorine species, wherein the second gas is configured to selectively etch Si relative to Sn;
e) subsequent to d), striking plasma in the substrate processing chamber with the second gas to selectively etch Si relative to Sn from the surfaces of the substrate processing chamber; and
f) extinguishing the plasma struck in e) and evacuating the substrate processing chamber.

2. The method of claim 1 , further comprising:
g) repeating a) to c) and d) to f) N times, where N is an integer greater than zero.

3. The method of claim 1 , wherein the second gas is selected from a group consisting of nitrogen trifluoride (NF 3 ), sulfur hexafluoride (SF 6 ), and carbon tetrafluoride (CF 4 ).

4. The method of claim 2 , wherein a) to g) are performed without a substrate located on a substrate support in the substrate processing chamber.

5. The method of claim 2 , further comprising pre-coating the surfaces of the substrate processing chamber with a material selected from a group consisting of silicon (Si) and silicon oxide (SiO x ) after g).

6. The method of claim 2 , wherein a) to c) are performed after d) to f) during each of the N times.

7. The method of claim 2 , wherein a) to c) are performed before d) to f) during each of the N times.

8. The method of claim 2 , further comprising:
prior to performing a) to g):
pre-coating a surface of the substrate processing chamber with a material selected from a group consisting of silicon (Si) and silicon oxide (SiO x ); and
performing a substrate treatment; and after g):
pre-coating the surface of the substrate processing chamber with a material selected from a group consisting of silicon (Si) and silicon oxide (SiO x ); and
performing a substrate treatment.

9. The method of claim 8 , wherein the substrate treatment comprises etching.

10. The method of claim 9 , wherein the substrate includes tin (Sn) and wherein Sn contamination is less than 1e10/cm2 after g).

11. The method of claim 1 , further comprising:
controlling a first pressure in the substrate processing chamber during b) within a first pressure range; and
controlling a second pressure in the substrate processing chamber during e) within a second pressure range, wherein the first pressure range is less than the second pressure range.

12. The method of claim 11 , wherein the first pressure range is from 1 to 30 mT and wherein the second pressure range is from 30 to 150 mT.

13. A substrate processing system for treating a substrate, comprising:
a processing chamber comprising chamber walls and a substrate support;
a gas delivery system configured to selectively deliver gases to the processing chamber, the gas delivery system comprising a first gas source comprising a first gas and a second gas source comprising a second gas, wherein the first gas is selected from a group consisting of silicon tetrachloride (SiCl 4 ), carbon tetrachloride (CCl 4 ), a hydrocarbon (C x H y where x and y are integers) and molecular chlorine (Cl 2 ), boron trichloride (BCl 3 ), and thionyl chloride (SOCl 2 ), wherein the first gas is configured to selectively etch tin (Sn) relative to silicon (Si), and wherein the second gas includes a fluorine species and is configured to selectively etch Si relative to Sn;
a plasma generator configured to selectively generate plasma in the processing chamber; and
a controller programed to perform a processing chamber clean comprising:
a) supplying the first gas;
b) striking plasma in the processing chamber with the first gas to selectively etch Sn relative to Si from surfaces of the processing chamber;
c) extinguishing the plasma struck in b) and evacuating the processing chamber;
d) supplying the second gas;
e) subsequent to d), striking plasma in the processing chamber with the second gas to selectively etch Si relative to Sn from the surfaces of the processing chamber; and
f) extinguishing the plasma struck in e) and evacuate the processing chamber.

14. The substrate processing system of claim 13 , wherein the controller is further configured to control the gas delivery system and the plasma generator to:
g) repeat a) to c) and d) to f) N times, where N is an integer greater than zero.

15. The substrate processing system of claim 13 , wherein the second gas is selected from a group consisting of nitrogen trifluoride (NF 3 ), sulfur hexafluoride (SF 6 ), and carbon tetrafluoride (CF 4 ).

16. The substrate processing system of claim 14 , wherein the controller is configured to control a robot to remove the substrate from the substrate support prior to performing a) to g).

17. The substrate processing system of claim 14 , wherein the controller is configured to control the gas delivery system and the plasma generator to pre-coat the surfaces of the processing chamber with a material selected from a group consisting of silicon (Si) and silicon oxide (SiO x ) after g).

18. The substrate processing system of claim 14 , wherein the controller is configured to control the gas delivery system and the plasma generator to perform a) to c) after d) to f) during each of the N times.

19. The substrate processing system of claim 14 , wherein the controller is configured to control the gas delivery system and the plasma generator to perform a) to c) before d) to f) during each of the N times.

20. The substrate processing system of claim 14 , wherein the controller is configured to control the gas delivery system and the plasma generator to:
prior to performing a) to g):
pre-coat a surfaces of the processing chamber with a material selected from a group consisting of silicon (Si) and silicon oxide (SiO x ); and
perform a substrate treatment; and
after g):
pre-coat the surface of the processing chamber with a material selected from a group consisting of silicon (Si) and silicon oxide (SiO x ); and
perform a substrate treatment.

21. The substrate processing system of claim 20 , wherein the substrate treatment comprises etching.

22. The substrate processing system of claim 21 , wherein the substrate includes tin (Sn) and wherein Sn contamination is less than 5e9/cm2 after g).

23. The substrate processing system of claim 13 , wherein the controller is configured to control the gas delivery system and the plasma generator to:
control a first pressure in the processing chamber during b) to a first pressure range; and
control a second pressure in the processing chamber during e) to a second pressure range, wherein the first pressure range is less than the second pressure range.

24. The substrate processing system of claim 23 , wherein the first pressure range is from 1 to 30 mT and wherein the second pressure range is from 30 to 100 mT.

Assignees

• Lam Res Corp

Inventors

• Yu Jengyi
• Tan Samantha Siamhwa
• Heo Seongjun
• Yuan Ge
• Kanakasabapathy Siva Krishnan

Classifications

• C23C16/4405

  Cleaning of reactor or parts inside the reactor by using reactive gases · CPC title

• H01J37/3288 Primary

  Maintenance · CPC title

• H01J37/32862 Primary

  In situ cleaning of vessels and/or internal parts · CPC title

• C21C5/441 Primary

  Equipment used for making or repairing linings · CPC title

• B23K10/003

  Scarfing, desurfacing or deburring · CPC title