membrane PS_PVAC thermal_property Microchannel Polymer Temasek_Lab Morphology Cross-section Polyimide Tungsten I-VSpectroscopy thermal_conductivity Writing Metal tip_bias_mode Leakage LithiumNiobate CuFoil SFAs NUSNNI MetalCompound DeflectionOptics HafniumDioxide MfmAmplitude self_healing ConductingPolymer ThermalDetectors BreastCancerCell Cancer block_copolymer Pvdf BiVO4 temp Hafnium_dioxide AM-KPFM