US5413670A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for plasma etching or cleaning with diluted NF3
Assignee: Versum Materials US LLC
•
Filing: 1993-07-08
•
Granted: 1995-05-09
•
Expires: 2013-07-08
Abstract
Abstract A method has been developed for the removal of silicon nitride and silicon dioxide, or other semiconductor materials from a surface of a wafer or CVD reactor. The method uses NF3, mixed with an electropositive diluent, preferably argon, at a given range of concentration, pressure, flowrate, and power to obtain the fastest possible etch rates. The etch rates of the film being processed can be caused to increase even as the concentration of NF3 in the diluent is decreased by choosing the proper diluent and operating conditions. Not only does this method increase the etch rate, thereby increasing the throughput of the reactor using this process, it also accomplishes this task at low concentrations of NF3 resulting in a lower cost.
Inventors
- 👤 John G. Langan
- 👤 Scott E. Beck
- 👤 Brian S. Felker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 22:36
CPC Classifications
H; H10; H10P; H10P70/00; H10P70/10; H10P70/12; C; C23; C23C; C23C16/00; C23C16/44; C23C16/4401; C23C16/4405; H10P50/00; H10P50/20; H10P50/28; H10P50/282; H10P50/283; Y; Y10; Y10S; Y10S134/00; Y10S134/902; Y10S438/00; Y10S438/905
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
71 words
A process for plasma etch-clean removal of films selected from the group consisting of silicon dioxide and silicon nitride which react with fluorine from a surface which comprises contacting said film with a plasma consisting essentially of approximately 10-25% nitrogen trifluoride in a diluent more electropositive than nitrogen trifluoride, at a pressure in the range of approximately 600-1700 mtorr, and a power in the range of approximately 0.4-1.4 W/cm 2 .
Claim 2
Dependent Claim
71 words
A process for plasma etch-clean removal of films selected from the group consisting of silicon dioxide and silicon nitride which react with fluorine from a surface which comprises contacting said film with a plasma consisting essentially of approximately 10-25% nitrogen trifluoride in a diluent more electropositive than nitrogen trifluoride, at a pressure in the range of approximately 600-1700 mtorr, and a power in the range of approximately 0.4-1.4 W/cm 2 .
Claim 3
Dependent Claim
23 words
The process of claim 1 wherein the diluent is selected from the group consisting of nitrogen, helium, argon, nitrous oxide and mixtures thereof.
Claim 4
Dependent Claim
15 words
The process of claim I wherein the nitrogen trifluoride is in the range of 10-18%.
Claim 5
Dependent Claim
12 words
The process of claim 1 wherein the pressure is approximately 800-1600 mtorr.
Claim 6
Dependent Claim
14 words
The process of claim 1 wherein the power is approximately 1.2 W/cm 2 .
Claim 7
Dependent Claim
15 words
The process of claim 1 wherein the power is at a frequency approximately 13.56 MHz.
Claim 8
Dependent Claim
54 words
A process for plasma etch-clean removal of silicon dioxide film from a surface which comprises contacting a silicon dioxide film with a plasma consisting essentially of approximately 15-25% nitrogen trifluoride in argon, at a pressure in the range of approximately 700-1700 mtorr, and a power in the range of approximately 0.4-1.4 W/cm 2 .
Claim 9
Dependent Claim
54 words
A process for plasma etch-clean removal of silicon dioxide film from a surface which comprises contacting a silicon dioxide film with a plasma consisting essentially of approximately 15-25% nitrogen trifluoride in argon, at a pressure in the range of approximately 700-1700 mtorr, and a power in the range of approximately 0.4-1.4 W/cm 2 .
Claim 10
Dependent Claim
54 words
A process for plasma etch-clean removal of silicon nitride film from a surface which comprises contacting a silicon nitride film with a plasma consisting essentially of approximately 10-25% nitrogen trifluoride in argon, at a pressure in the range of approximately 700-1700 mtorr, and a power in the range of approximately 0.4-1.4 W/cm 2 .
Claim 11
Dependent Claim
54 words
A process for plasma etch-clean removal of silicon nitride film from a surface which comprises contacting a silicon nitride film with a plasma consisting essentially of approximately 10-25% nitrogen trifluoride in argon, at a pressure in the range of approximately 700-1700 mtorr, and a power in the range of approximately 0.4-1.4 W/cm 2 .
References Cited (Backward Citations)
US4412119A
Cited
US4522681A
Cited
US4654112A
Cited
US4711698A
Cited
JPS6311674A
Cited
US5000113A
Cited
US4981551A
Cited
JPH01194423A
Cited
US4904341A
Cited
US5209803A
Cited
US5286297A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-05-08 | 1998-11-07 | 1999-05-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-05-08 | 2002-11-07 | 2003-05-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-05-08 | 2006-11-07 | 2007-05-09 | $7700.00 | Window Closed / Lapsed |