Clean chemistry for tungsten/tungsten nitride gates
A process and composition for cleaning debris from a stack etch/ion implanted CMOS device which includes a tungsten gate conductor. The composition includes sulfuric acid and hydrogen peroxide in a volume ratio of at least about 6:1. In the process the composition contacts the CMOS device at atmospheric pressure and a temperature of between about 70° C. and about 90° C.
1 . A process of removing residue from a complementary metal oxide semiconductor (CMOS) device which includes a tungsten gate conductor which has been subject to stack etch/ion implantations and photoresist stripping steps comprising the step of contacting a CMOS device which includes a tungsten gate conductor with a cleaning composition comprising sulfuric acid and hydrogen peroxide present in a volume ratio of at least about 6:1, said contact occurring at atmospheric pressure and a temperature of between about 70° C. and about 90° C.
2 . A process in accordance with claim 1 wherein said volume ratio of said sulfuric acid to said hydrogen peroxide is at least about 6:1 and about 100:1.
3 . A process in accordance with claim 1 wherein said volume ratio of sulfuric acid to hydrogen peroxide is in the range of between about 6:1 and about 10:1.
4 . A process in accordance with claim 1 wherein said volume ratio of sulfuric acid to hydrogen peroxide about 8:1.
5 . A process in accordance with claim 1 wherein contact of said composition with said CMOS device occurs over a period of between about 1 minute and about 10 minutes.
6 . A process in accordance with claim 5 wherein said period of time is in the range of between about 2 minutes and about 5 minutes.
7 . A process in accordance with claim 1 comprising pre-mixing of said sulfuric acid and said hydrogen peroxide whereby said cleaning composition is formed.
8 . A process in accordance with claim 1 comprising in-situ mixing of said sulfuric acid and said hydrogen peroxide whereby said cleaning composition is formed.
9 . A process in accordance with claim 1 wherein said cleaning composition consists essentially of sulfuric acid and hydrogen peroxide.
10 . A composition which comprises sulfuric acid and hydrogen peroxide present in a volume ratio of at least about 6:1.
11 . A composition in accordance with claim 10 wherein said volume ratio is in the range of between 6:1 and about 100:1.
12 . A composition in accordance with claim 11 wherein said volume ratio is in the range of between about 6:1 and about 10:1.
13 . A composition in accordance with claim 12 wherein said volume ratio is about 8:1.
14 . A composition which consists essentially of sulfuric acid and hydrogen peroxide present in a volume ratio of at least about 6:1.
15 . A composition in accordance with claim 14 wherein said volume ratio is in the range of between about 6:1 and about 100:1.
16 . A composition in accordance with claim 15 wherein said volume ratio is in the range of between about 6:1 and about 10:1.
17 . A composition in accordance with claim 16 wherein said volume ratio in about 8:1.