Bis(trifluoromethyl)carbinol-Substituted Polynorbornenes: Dissolution Behavior

Abstract

Alicyclic polymers, such as substituted polynorbornene (PNB), are expected to be one potential material solution for providing transparent photoresist polymer resins for photolithography at 193 and 157 nm wavelengths. In this work, the dissolution behavior of bis(trifluoromethyl)carbinol-substituted polynorbornene (HFAPNB) in aqueous alkaline solutions as a function of polymer molecular weight is explored. Surprisingly, it was found that the dissolution rate of bis(trifluoromethyl)carbinol-substituted polynorbornene increased with increasing molecular weight over the range from approximately 10,000 to 100,000 Mw. Experimental results show that this polymer displays strong hydrogen bonding in the solid film form and that such hydrogen bonding is disrupted as the polymer molecular weight is increased. On the basis of this evidence, an explanation for this unusual dissolution behavior based upon disruption of hydrogen bonding is presented.