The influence of residual casting solvent on the dissolution behavior of diazonaphthoquinone resists

Residual casting solvent present in resist films can have a profound effect on their dissolution behavior. We have used a radiolabeling technique to make quantitative measurements of solvent remaining in spin cast films after they have undergone different baking protocols. Films of poly (3-methyl-4-hydroxystyrene) were found to contain a significant fraction of propylene glycol methyl ether acetate (as much as 50% by weight) depending on the baking conditions. Films that were 1000 A thick contained a higher percentage of residual solvent than films that were 1 .tm. The solvent concentration in films containing a mixture of polymer and photoactive compound was a maximmum for films containing 5 wt% PAC.