FrictionalForce kelvin probe force microscopy Sapphire PiezoelectricForceMicroscopy NUSNNI WWafer Oxide small_scan molecular_beam Phenanthrene piezoelectric force microscopy Pinpoint PFM organic_polymer GaP VinylAlcohol SurfaceChange Bio Magnetic Force Microscopy 2d_materials NusEce Hafnia fifber CHRYSALIS_INC IMT_Bucharest C_AFM IRDetector PyroelectricDetector Layer Ecoli AM_SKPM Ucl cannabidiol FM_KPFM GalliumPhosphide Adhesive