Hello, I am trying to find an anisotropic silicon etchant which also doesn't attack Aluminum. I was told that TMAH doesnot attack Al. I tried etching under the following conditions. Concentration - TMAH 25% - rest water. Temperature - 80C and also at 100C. The Aluminum was removed under less than 15 mins. I would like any information from about the etch conditions and also any other etchant suitable for the purpose. Thank You in advance, Nandakumar. -- K.Nandakumar. Tel : (216) 368 4109 (Lab) 2504, Derbyshire Rd, #2, (216) 371 6746 (res) Cleveland, OH 44106. Fax: (216) 368 2668.