Optimization of PDMS network for a fast response and sensitive actuation material applied in a MEMS spatial light modulator

The cross-linked networks of linear vinyl-terminated poly(dimethylsiloxane) (PDMS) with trimethylsiloxy-terminated methyhydrosiloxane-dimethylsiloxane copolymer (cross-linker) were investigated by tuning the cross-linker concentration, the chain length of linear PDMS and the functionality of the cross-linker. Response time and elastic modulus of the cross-linked PDMS elastomer were characterized by home-made measurement systems and analyzed based on their network topologies. An optimized PDMS elastomer, which has response time of 9 mu s and elastic modulus of 601 kPa, was utilized as the actuation material in a MEMS spatial light modulator (SLM). The fabrication processes were described. This polymer based SLM has shown fast response time (9 mu s) and successfully diffracted light into higher orders with 84% first-order diffraction efficiency.