The concurrent radical and cationic polymerization system was studied for a photoresist. This study illustrates an approach an to the formation of a hybrid resist by incorporating epoxy into acryl monomer or vinyl ether. The effects of photoinitiator concentration, monomer type, oxygen inhibition, autocleavage kinetics and photolysis of onium salt were also studied for the optimum formation of resist. The results demonstrate the importance of selecting the correct thickness and photoinitiator concentration to achieve maximum curing rate and enhanced physical properties and how the value of this selection is directly related to the formulation of photoresist. Various compositions based on photo calorimetric studies concerned hybrid systems of photopolymerization reaction. The pattern of microlithography was formed up to 2.5 ㎛ with DPHA/ECN/BDK/DIOPF6=10/6.5/0.2/0.2. Microlithography ranging from 0.8 ㎛ to 2 mm thickness in hybrid photoresist was formed with epoxy concentration as high as 40 weight percentage.