Design concepts of single-layer-resists for VUV lithography

We have studied the design of single-layer-resists for VUV lithography. From the point of view of transparency, phenol resins may be used as well as methacrylate polymers in VUV lithography. The resulting high contrast is thought due to the effect of direct photodecomposition of base polymer and photo-deprotection in addition to the deprotection by acids. We are planning to investigate the polymers with higher transparency (ex. halogen-substituted phenol resins) and the polymer structure inhibiting the crosslinking.