Etching a substrate: processes – Nongaseous phase etching of substrate – Etching inorganic substrate
Patent
1997-07-23
1999-01-05
Martin, Roland
Etching a substrate: processes
Nongaseous phase etching of substrate
Etching inorganic substrate
252 791, 252 792, 252 794, 510175, C11D 904, B44C 122, C03C 1500
Patent
active
058558055
ABSTRACT:
The microetching and cleaning of copper clad substrates in printed wiring board production with solutions containing alkali metal persulfate and sulfuric acid is controlled to provide slower and more consistent copper etch rates by the presence of high proportions of alkali metal sulfate or an alkali metal sulfate/bisulfate mixture in the solutions, in a mole ratio of persulfate to sulfate or sulfate/bisulfate mixture of 1:0.1 to 1:10. When bisulfate is present with the sulfate, the sulfate will comprise at least about 10 mole % of the sulfate/bisulfate mixture. A surfactant may be present in the solutions to aid wettability on the copper clad substrates.
REFERENCES:
patent: 3137600 (1964-06-01), Margulies et al.
patent: 3140203 (1964-07-01), Grunwald
patent: 3227517 (1966-01-01), Leaver et al.
patent: 3305135 (1967-02-01), Lindstrom
patent: 3373114 (1968-03-01), Grunwald
patent: 3470044 (1969-09-01), Radimer
patent: 3887405 (1975-06-01), Fong et al.
patent: 3988254 (1976-10-01), Mori
patent: 4507220 (1985-03-01), Streit et al.
Lore, "Cleaning Copper Chemically" 1PC-TP-251 Paper (13 pages), Sep. 17-21, 1978, San Diego, CA.
Baker Patrick C.
FMC Corporation
Martin Roland
Monroe Bruce M.
LandOfFree
Microetching and cleaning of printed wiring boards does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Microetching and cleaning of printed wiring boards, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Microetching and cleaning of printed wiring boards will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-859141