kelvin probe force microscopy GaN TungstenDeposition NUS Imprint Blend lithography light_emission FrictionalForceMicroscopy H-BN SingleLayer Gallium HighAspect InLiquid Hexatriacontane PMNPT BreastCancerCell DOE Yeditepe_University graphene_hybrid Titanate Tungsten_disulfide Lateral Photovoltaics phase_change Leakage Magnets EFM C60H122 UnivMaryland Vortex Chrome Adhesive Ptfe Copolymer