Study on organosilicon positive resist. I. Syntheses and characterization of silsesquioxane, siloxane, and silmethylene polymers with phenolic hydroxy groups

Silsesquioxane, siloxane, and silmethylene polymers with phenolic hydroxy groups were prepared in order to obtain alkali-soluble organosilicon polymers. These polymers have structures in which the phenol moieties are separated by one carbon from the silicon. The hydroxy groups were protected as methoxy groups in polymerization processes, then were changed into hydroxy groups by a reaction with trimethylsilyl iodide followed by alcoholysis. In the course of discussion on the characteristics of these polymers, silsesquioxane with phenolic hydroxy groups is found to possess excellent properties for matrix resins of alkalidevelopable organosilicon resists, such as O2RIE resistance and heat resistance.