Alkaline Etch Medium and Photoresist Stripper
Original Publication Date: 1988-Feb-01
Included in the Prior Art Database: 2005-Feb-14
An alkaline sodium hydroxide-based etch medium is described which is suitable for etching titanium and aluminum layers as well as for stripping totally cross-linked novolak-based photoresist materials. The etch medium is composed as follows: 200 to 500 g/l sodium hydroxide 30 to 80 g/l ethanolamine 80 g/l gluconic acid lactone 1 l water The etch medium is suitable for etching titanium, with the etch rate depending on existing TiO2 layers, if any. The bath temperature generally ranges from about 80 to 120oC, a bath temperature of, say, 90oC leading to a titanium etch rate of about 300 nm/minute. The etch rate of aluminum is about twice as high.