AM-KPFM PatternedSapphireSubstrat atomic_steps Alloy Annealed Collagen PvdfBead PolyvinylAcetate Nanotechnology Ananth frequency_modulation PtfeMembrane Hair NUS Graphite silicon_carbide bias_mode Adhesive SingleLayer Organic MechanicalProperty FailureAnlaysis Mosfet PFM LiftMode Modulus I-VSpectroscopy STM HighAspect Tape P3HT Stiffness polyvinyl acetate Semiconductor GlassTemp