Polyimide Vac Leakage mfm_amplitude ito_film Materials SolarCell TipBiasMode LiftMode FrequencyModulation Ceramic HighResolution LeakageCurrent ThinFilm ScanningTunnelingMicroscopy hydrocarbon molecule Austenite Sidewall MolybdenumDisulfide Monisha EPFL Polystyrene molecular_beam LithiumNiobate ThermalProperties FM_KPFM silicon_carbide Spincast MeltingPoint Device thermoplastic_elastomers Display Pinpoint PFM HfO2