Chemical amplification positive deep-UV resist using partially tetrahydropyranyl-protected polyvinylphenol

摘要

Chemical amplification positive resists using tetrahydropyranyl- protected polyvinylphenol (THP-M) were investigated for deep UV lithography. Infrared spectroscopy measurements showed that THP-M in the resist film cannot be completely deprotected by photo- generated acid. This causes a poor developability of the resist containing highly tetrahydropyranyl (THP)-protected polyvinylphenol in an aqueous base developer. In order to improve the developability in the pure aqueous base developer, we utilized partially THP-protected polyvinylphenol. To determine the optimum protection degree, we examined the relation between the dissolution rate of THP-M films and THP-protection degree in developers. A resist formulated from 20% THP-protected polyvinylphenol and bis(tert-butylphenyl)iodonium triflate resolved 0.30 $mu@m line-and-space patterns with the aqueous base development using a KrF excimer laser stepper with a dose of 46 mJ/cm$+2$/.