I will be trying next week for my lift-off work, the image reversal process for aluminum (and other metallizations) as described by Meier et al., "Fabrication of an all-refractory circuit using lift-off with image-reversal photoresist", IEEE Transactions on Magnetics, Vol 27, No. 2, March 1991. I will be using AZ 5214-E and AZ Developer. The latter is the only developer, so I'm told, that does NOT etch aluminum. I do know that AZ 351 did etch my aluminum films undesirably on previous processing steps, so I have to abandon that developer. Good luck, Thomas Wilson Physics Marshall University ----Original Message----- From: William Lanford-Crick Sent: Tuesday, August 23, 2005 11:13 AM To: 'General MEMS discussion' Subject: RE: [mems-talk] Problems with lift-off using S1813 photoresist In my experience, MIF 319 etched aluminum very fast. I used to use MIF 319 to remove LOR-5B after lifting off Al with Acetone (using bilayer). It etched the Al very rapidly. -Bill