piezoelectric force microscopy Ptfe InorganicCompound CalciumHydroxide Etch Ram CarbonNanotube phase_change Wonseok FrictionalForceMicroscopy ThinFilm Imprint HACrystal Ucl PatternedSapphireSubstrat Nickel Electronics NTU C_AFM fifber OxideLayer Composite PECurve Glass nanobar medical EvatecAG polymeric_arrays Conductance Wafer Boron PANI FM_KPFM Pyroelectric mechanical_property