Claims
- 1. A method for etching treatment onto a silicon oxide film formed on a substrate with a resist mask, comprising the steps of:providing an etchant with a combination having hydrofluoric acid of 8 percent by weight to 19 percent by weight and ammonium fluoride of 12 percent by weight to 42 percent by weight, said combination having a hydrogen ion concentration of 10−6.0 mol/L to 10−1.8 mol/L; etching said silicon oxide film at a rate of at least 200 nm/min; and, setting the film-reduction rate of said resist mask to at most 50 nm/min.
- 2. The method for etching treatment onto a silicon oxide film formed on a substrate with a resist mask as in claim 1 wherein said etching rate is set by adjusting the temperature in said etchant.
- 3. The method for etching treatment onto a silicon oxide film formed on a substrate with a resist mask as in claim 1 wherein setting said film-reduction rate of said resist mask is controlled by said hydrogen ion concentration.
- 4. The method for etching treatment onto a silicon oxide film formed on a substrate with a resist mask as in claim 1 further comprising the step of providing said etchant with a surfactant of 0.0001 percent by weight to 1 percent by weight.
- 5. The method for etching treatment onto a silicon oxide film formed on a substrate with a resist mask as in claim 1 wherein providing said etchant with hydrofluoric acid of 15 percent by weight to 19 percent by weight.
- 6. The method for etching treatment onto a silicon oxide film formed on a substrate with a resist mask as in claim 5 further comprising the step of providing said etchant with a surfactant of 0.0001 percent by weight to 1 percent by weight.
Priority Claims (2)
Number |
Date |
Country |
Kind |
8-338701 |
Dec 1996 |
JP |
|
PCT/JP97/04608 |
Dec 1999 |
JP |
|
CONTINUATION DATA
This application hereby claims the benefit under Title 35, United States Code, §120, and is a Continuation of U.S. application Ser. No. 09/125,44, now U.S. Pat. No. 6,585,910 filed on Mar. 26, 1999 and accepted on Jul. 1, 2003 and is hereby incorporated by reference.
US Referenced Citations (4)
Number |
Name |
Date |
Kind |
4795582 |
Ohmi et al. |
Jan 1989 |
A |
5496485 |
Maternaghan |
Mar 1996 |
A |
5972123 |
Verhaverbeke |
Oct 1999 |
A |
6068788 |
Kezuka et al. |
May 2000 |
A |
Foreign Referenced Citations (10)
Number |
Date |
Country |
50-93240 |
Jul 1975 |
JP |
53-126272 |
Apr 1978 |
JP |
4-7832 |
Jan 1992 |
JP |
4-317331 |
Nov 1992 |
JP |
5-82503 |
Apr 1993 |
JP |
06333912 |
Dec 1994 |
JP |
07086229 |
Mar 1995 |
JP |
07115077 |
May 1995 |
JP |
7-506616 |
Jul 1995 |
JP |
WO 9418696 |
Aug 1994 |
WO |
Continuations (1)
|
Number |
Date |
Country |
Parent |
09/125440 |
Aug 1998 |
US |
Child |
10/609834 |
|
US |