Claims
- 1. A method of preparing a thin film resistor comprising the steps of:
- forming a thin film comprising at least one metal selected from the group consisting of Cr and Si on an oxide film;
- covering a predetermined partial area of said thin film with a photoresist to thereby form a masked portion of said thin film and an exposed portion of said thin film;
- converting a gas mixture comprising a fluorine compound gas and oxygen to plasma in a first vessel, said gas mixture comprising more than 70 vol % of oxygen based on the sum of the oxygen and fluorine compound, said fluorine compound being capable of forming fluorine activated by plasma conversion;
- introducing said plasma into a second vessel which contains said oxide film having thereon said thin film and said photoresist; and
- removing said exposed portion of said thin film from said oxide film by exposing said exposed portion of said thin film to said plasma.
- 2. A method of preparing a thin film resistor according to claim 1, wherein said compound comprising at least one metal is a compound comprising nitrogen.
- 3. A method of preparing a thin film resistor according to claim 1, wherein said fluorine compound gas is carbon tetrafluoride.
- 4. A method of preparing a thin film resistor according to claim 1, wherein said oxide film is a SiO.sub.2 film or a phosphosilicate glass film.
- 5. A method of preparing a thin film resistor comprising the steps of:
- forming a thin film comprising at least one metal selected from the group consisting of Cr and Si on an oxide film;
- covering a predetermined partial area of said thin film with a photoresist to thereby form a masked portion of said thin film and an exposed portion of said thin film;
- converting a gas mixture comprising carbon tetrafluoride and oxygen to plasma in a first vessel, said gas mixture comprising more than 70 vol % of oxygen based on the sum of carbon tetrafluoride and oxygen;
- introducing said plasma into a second vessel containing said oxide film having thereon said thin film and said photoresist; and
- removing said exposed portion of said thin film from said oxide film by exposing said exposed portion of said thin film to said plasma.
- 6. A method of preparing a thin film resistor comprising the steps of:
- forming a thin film comprising at least one metal selected from the group consisting of Cr and Si on an oxide film;
- covering a predetermined partial area of said thin film with a photoresist to thereby form a masked portion of said thin film and an exposed portion of said thin film;
- converting a gas mixture comprising a fluorine compound gas and oxygen to plasma in a first vessel, said gas mixture having more than 70 vol % of oxygen based on the sum of the oxygen and fluorine compound, said fluorine compound being capable of forming fluorine activated by plasma conversion;
- introducing said plasma into a second vessel containing said oxide film having thereon said thin film and said photoresist;
- removing said exposed portion of said thin film by exposing said exposed portion of said thin film to said plasma and wherein the removing step is is effective to etch said thin film at a faster rate than said oxide film; and
- removing said photoresist from said predetermined area of said thin film.
- 7. A method as in claim 6, wherein said faster rate is faster by a factor of about 16.
- 8. A method as in claim 1, wherein said gas includes said fluorine compound gas introduced at a flow rate of 40 standard cubic cm/min, said oxygen introduced at a flow rate of 360 standard cubic cm/min and wherein said plasma etching is carried out under a pressure of 30 Pa and a power of 500 W.
- 9. A method as in claim 5, wherein said gas includes said fluorine compound gas introduced at a flow rate of 40 standard cubic cm/min, said oxygen introduced at a flow rate of 360 standard cubic cm/min and wherein said plasma etching is carried out under a pressure of 30 Pa in power of 500 W.
- 10. A method according to claim 1, wherein the method further comprises a removing step including removing the photoresist remaining on the predetermined area of the thin film.
- 11. A method according to claim 5, wherein the method further comprises a removing step including removing the photoresist remaining on the predetermined area of the thin film.
Priority Claims (1)
Number |
Date |
Country |
Kind |
3-251925 |
Sep 1991 |
JPX |
|
Parent Case Info
This is a continuation of U.S. application Ser. No. 07/952,408, filed Sep. 30, 1994, now abandoned.
US Referenced Citations (10)
Foreign Referenced Citations (7)
Number |
Date |
Country |
0101632 |
Feb 1984 |
EPX |
50-38200 |
Dec 1975 |
JPX |
53-25442 |
Mar 1978 |
JPX |
60-261101 |
Dec 1985 |
JPX |
63-119549 |
Nov 1986 |
JPX |
63-229717 |
Sep 1988 |
JPX |
8300256 |
Jan 1983 |
WOX |
Non-Patent Literature Citations (2)
Entry |
Foreign Patent Document: Japanese 63-216960 dated Sep. 1988, English Abstract, Not Translated. |
IBM Technical Disclosure Bulletin, vol. 24, No. 6, Nov. 1981, pp. 2962-2963. |
Continuations (1)
|
Number |
Date |
Country |
Parent |
952408 |
Sep 1994 |
|