Mixed Resin Photoresist System for Mid and Deep Ultraviolet
Original Publication Date: 1983-Jan-01
Included in the Prior Art Database: 2005-Feb-06
Conventional diazonapthoquinone ("DQ") sensitizer containing photo-resists contain a casting solvent, a novolak resin (typically based upon a cresol, phenol or cresylic acid), and a photoactive compound (PAC) which is photolyzed from a hydrophobic R (DQ)(n) form to a carboxylic acid form (R(X-COOH)(n)), which is then soluble in an aqueous base. It has been found that a mixture of several novolak resins, rather than a single resin, provides an improved performance. In particular, a high molecular weight novolak resin based upon a cresylic acid (such as VARCUM (Trademark of Reichhold Chemicals Inc.) 6000-x series resins, number average molecular weight approx.