AM_KPFM Filter Vac GaN #Materials lithography Workfunction Treatment Dopped solar_cell Leakage PinpointPFM gallium_nitride Grain pinpoint mode Graphite MolecularSelfAssembly Materials PrCurve CuFoil Au111 tip_bias_mode China ULCA temp_control Pattern FM_SKPM GaP contact chemical_compound plastic InsulatorFilm temp INSPParis semifluorinated_alkane