Surface and electromechanical properties of polydimethylsiloxane films prepared by modified molding technique

摘要

In this paper, we report surface and electromechanical properties of polydimethylsiloxane (PDMS) films prepared by a modified molding technique. The film with thickness = 4 μm was deposited on oxidized silicon wafer by the modified molding technique and corresponding elastic modulus of the bulk PDMS materials is equal to 36 kPa. Surface morphology of the film was examined by optical interferometer and Scanning Electron Microscope (SEM). Its roughness is ～ 10 nm and wave-liked structures were locally observed on the film surface. In order to investigate electromechanical performance of the film, sandwich structured multilayer films Au (patterned electrodes, 150 nm) /PDMS (4 μm) /Au (top un-patterned electrode, 50 nm) were deposited on the oxidized silicon wafer. The displacement ratios of the PDMS film parallel to electric fields were characterized from 0 V/μm to 52.5 V/μm and maximum value of the displacement ratio reaches ～ 5.0 %. Meanwhile, the rising and falling response time of the PDMS films are reported as a function of applied electric fields. Since the good light reflection of top gold electrode and displacement ratio of the sandwich-structured films, the multilayer films device might be a proper candidate for the application of spatial light modulator.