Claims
- 1. A method of depositing an adherent metal film to at least one surface of a polyimide substrate comprising the steps of:(a) exposing at least one surface of the polyimide substrate to a reactive gas plasma that results in carboxyl or carboxylate group formation, and that provides a level of ion bombardment of at least about 9×1017 eV/liter-atm, wherein the level of ion bombardment is represented by the equation: (q)×(n+)×(øf)/p; where q=the unit electronic charge (equal to 1 for units of e/V/liter-atm); n+=the number density of positive ions in the plasma (liter−1); (øf)=the potential difference between the plasma and the polyimide surface (volts); and p=pressure in atmospheres; and (b) then depositing a metallic film onto the ion-bombarded surface without intervening exposure to air.
- 2. The method of claim 1 wherein the plasma provides a level of ion bombardment in the range of from about 9×1017 eV/liter-atm to about 25×1017 eV/liter-atm.
- 3. The method of claim 1 wherein the ions are generated by a glow discharge process and wherein the metal film is deposited on the ion-bombarded surface by a vacuum metallization process.
- 4. The method of claim 1 wherein said deposited metallic film is a copper film.
- 5. The method of claim 4 wherein the ions are generated by a DC glow discharge process; and wherein said copper film is deposited on the ion-bombarded surface by a vacuum metallization process.
- 6. The method of claim 5 wherein the reactive gas plasma is an oxygen plasma having a pressure of between 0.01 and 0.30 torr; andwherein the substrate is bombarded with oxygen ions formed by subjecting the oxygen to a power density of from about 0.05 to about 0.5 w/cm2.
- 7. The method of claim 1 wherein said metallic film is a chromium film; and wherein said chromium film is deposited on the ion-bombarded surface by a vacuum metallization process.
- 8. A method of depositing a copper film on a surface of a polyimide substrate comprising the steps of:(a) exposing the polyimide substrate to an oxygen plasma comprising oxygen ions that provide a level of ion bombardment of at least about 9×1017 eV/liter-atm, wherein the level of ion bombardment is represented by the equation: (q)×(n+)×(øf)/p; where q=the unit electronic charge (equal to 1 for units of e/V/liter-atm); n+=the number density of positive ions in the plasma (liter−1); (øf)=the potential difference between the plasma and the polyimide surface (volts); and p=pressure in atmospheres; and (b) then depositing a copper film onto the surface without intervening exposure to air.
- 9. The method of claim 8 wherein the ions are generated by a flow discharge process and wherein the copper film is deposited on the ion-bombarded surface by a vacuum metallization process.
- 10. The method of claim 9 wherein the ions are generated by a DC glow discharge process.
- 11. The method of claim 9 wherein the reactive plasma comprises oxygen ions.
- 12. The method of claim 11wherein the reactive plasma has a pressure of between about 0.01 and 0.30 torr; wherein the substance is bombarded with said oxygen ions that have been formed by subjecting oxygen gas to a power density of at least about 0.05 w/cm2; and wherein the substrate is exposed to the reactive gas plasma for at least 5 seconds.
- 13. The method of claim 12 wherein the plasma pressure is between about 0.05 and 0.0.09 torr.
- 14. The method of claim 12 wherein the power density is from about 0.05 w/cm2.
- 15. The method of claim 12 wherein the substrate is exposed to the reactive gas plasma for about 5 to about 60 seconds.
CROSS REFERENCE TO RELATED APPLICATION
This application is a divisional of application Ser. No. 08/837,859, filed Apr. 22, 1997 now U.S. Pat. No. 6,194,076.
US Referenced Citations (5)
Foreign Referenced Citations (2)
Number |
Date |
Country |
13-21687 |
Dec 1989 |
JP |
32-17823 |
Sep 1991 |
JP |
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