METHODS AND APPARATUS FOR IN-SITU CHAMBER DRY CLEAN DURING PHOTOMASK PLASMA ETCHING

• US 20090325387A1
• Filed: 06/26/2008
• Published: 12/31/2009
• Est. Priority Date: 06/26/2008
• Status: Abandoned Application

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Ibrahim, Ibrahim, Mao, Zhigang, Knick, David, Chandrahood, Madhavi, Bivens, Darin, Kumar, Ajay, Grimbergen, Michael, Chen, Xiaoyi
• Application Number:
  US12/147,341
• Publication Number:
  US 20090325387A1
• Time in Patent Office: Days
• US Class Current: 438/710
• CPC Class Codes: G03F 1/80 Etching
• CPC Class Codes: H01J 37/32862 In situ cleaning of vessels and/or internal parts

Abstract

Embodiments of the invention include method for in-situ chamber dry clean after photomask plasma etching. In one embodiment, the method includes placing a photomask upon a support pedestal, introducing a process gas into a process chamber, forming a plasma from the process gas, etching a chromium containing layer disposed on the photomask in the presence of the plasma, removing the photomask from the support pedestal, placing a dummy substrate on the pedestal and performing an in-situ dry cleaning process by flowing a cleaning gas containing O₂ through the process chamber while the dummy substrate is disposed on the support pedestal.

Claims

1. A method for in-situ chamber dry clean after photomask plasma etching, comprising:

placing a photomask upon a support pedestal;

introducing a process gas into a process chamber;

forming a plasma from the process gas;

etching a chromium containing layer disposed on the photomask in the presence of the plasma;

removing the photomask from the support pedestal; and

performing an in-situ dry cleaning process by flowing a cleaning gas containing O₂ through the process chamber while the dummy substrate is disposed on the support pedestal.

2. The method of claim 1 further comprising:

using an end point detection device to determine if by-products of the etch are sufficiently removed from the chamber.

3. The method of claim 1, wherein the cleaning gas does not contain chlorine.

4. The method of claim 1, wherein the cleaning gas further comprises chlorine.

5. The method of claim 3, wherein the cleaning gas comprises oxygen provide at a rate of about 50 to about 1000 sccm.

6. The method of claim 2, wherein the end point detection device monitors optical emission spectra.

7. The method of claim 1, wherein a flow rate of oxygen in the cleaning gas is between about 50 to about 1000 sccm, and wherein a flow rate of chlorine in the cleaning gas about 25 to about 500 sccm.

8. The method of claim 1, wherein a flow rate of oxygen in the cleaning gas is between about 50 to about 400 sccm, and wherein a flow rate of chlorine in the cleaning gas about 50 to about 400 sccm.

9. The method of claim 1, wherein a flow rate of oxygen in the cleaning gas is between about 100 sccm, and wherein a flow rate of chlorine in the first cleaning gas about 100 sccm.

10. The method of claim 1, wherein the dry clean process is performed in the absence of bias power.

11. The method of claim 1, wherein the process chamber has an internal pressure during the dry cleaning process of about 2 to 50 mTorr.

12. The method of claim 1, wherein the RF power is utilized to maintain a plasma formed from the cleaning gas, the RF power applied a range between 150 and 1500 W in absence of bias power.

13. The method of claim 12, wherein the RF power is applied to outer and inner coils positioned adjacent the chamber at a power ratio of outer to inner coils of between about 15 to about 85 percent.

14. A method for in-situ chamber dry clean after photomask plasma etching, comprising:

placing a photomask upon a support pedestal disposed in a process chamber;

plasma etching a chromium containing layer disposed on the photomask while applying bias power;

removing the etched photomask from the process chamber; and

performing an in-situ dry cleaning process without bias power in the presence of a cleaning plasma formed from a cleaning gas containing O₂ after the etched photomask has been removed from the process chamber.

15. The method of claim 14, wherein performing the in-situ dry cleaning process further comprises:

providing Cl₂ in the cleaning gas.

16. The method of claim 15, wherein a flow rate of oxygen in the cleaning gas is between about 50 to about 1000 sccm, and wherein a flow rate of chlorine in the cleaning gas about 25 to about 500 sccm.

17. The method of claim 15, wherein a flow rate of oxygen in the cleaning gas is between about 50 to about 400 sccm, and wherein a flow rate of chlorine in the cleaning gas about 50 to about 400 sccm.

18. The method of claim 16, wherein the RF power is utilized to maintain the cleaning plasma, the RF power applied a range between 150 and 1500 W in absence of bias power.

19. The method of claim 16, wherein the RF power is applied to outer and inner coils positioned adjacent the chamber at a power ratio of outer to inner coils of between about 15 to about 85 percent.

20. The method of claim 14 further comprising:

placing a dummy substrate on the pedestal after the etched photomask has been removed; and

performing the in-situ dry clean while the dummy substrate is disposed on the support pedestal.