Novel low temperature curable photo-sensitive insulator

This paper reports on our development of a low temperature curable photo-sensitive insulator. The design concept of our photo-sensitive insulator is based on a phenolic resin as the main component to perform good lithography and a polymeric cross-linker containing an epoxy functional unit. This polymeric epoxy cross-linker can decrease wafer stress by controlling the distance between cross-linked points with phenolic resin. Moreover, our photo-sensitive insulator contains naphthoquinone diazide (DNQ) compounds commonly used in positive tone resists. Through these concepts, our low temperature curable (around 200 °C) photo-sensitive insulator shows low residual stress (<20MPa), low elastic modulus (<1.8GPa), good chemical resistance and good lithography performance.