Single Layer Lift-Off Process
Original Publication Date: 1979-Sep-01
Included in the Prior Art Database: 2005-Feb-20
This photolithographic lift-off technique provides an improved single layer lift-off profile (*) and avoids the necessity of using environmentally unsafe organic solvents. The lift-off structure is prepared as follows: 1. Preclean substrate surface using any desired photolithographic cleaning process. 2. Precoat substrate with a photoresist adhesion promoter, if desired. 3. Apply a layer of positive diazo photoresist to a thickness of about 1.7 microns. Suitable photoresists are the phenolformaldehyde novolak resin, 2-diazo- 1-oxo- naphthalene- 5sulfonic acid diester of dihydroxybenzophenone containing types. 4. Bake the photoresist for about 5 minutes on a hot plate at about 75 degrees C. 5. Soak the coated substrate in an aqueous solution of 0.