vertical_PFM mechanical_property Polydimethylsiloxane Nickel hetero_structure OpticalWaveguide PrCurve UnivMaryland ForceDistanceSpectroscopy AmplitudeModulation Spain SiliconOxide PS_LDPE SSRM light_emission MeltingPoint FloppyDisk Hexylthiophene ThermalProperties Mosfet SingleLayer Nanostructure Composition CopperFoil FM-KPFM Beads PDMS AtomicSteps Nanopattern frequency_modulation align Roughness Tape Permalloy ShenYang