ElectrostaticForceMicroscopy PvdfFilm thermal_property PolyimideFilm Ananth Solar Ito semifluorinated_alkanes Composite Chrome Sphere Tin sulfide ScanningSpreadingResistanceMicroscopy PFM InsulatorFilm TransitionMetal pinpoint mode Copper HfO2 Ucl FAFailureAnlaysis SRAM Protein HDD Spain Ceramic Cell GlassTemperature GranadaUniv biocompatible Writing conductive fe_nd_b ContactModeDots PinpointPFM