kelvin probe force microscopy Piranha Crystal GaN Zagreb Wildtype pulsed_laser_deposition Optic HanyangUniv norganic Thermal rubber Gong HighResolution FailureAnlaysis Polyimide CP-AFM YszSubstrate CeramicCapacitor Silver UnivMaryland block_copolymer Cell HexagonalBoronNitride Microchannel Graphite Defects Ferrite temperature_control Oxidation H-BN CopperFoil HumanHair Annealing Etch