GaN TappingMode HexagonalBN Kevlar AtomicSteps HydroGel Hafnia YszSubstrate PvdfBead Resistance temperature controller AFM Mechanical FrictionForce Defect FAPbI3 Sapphire LiquidImaging Sidewall FastScan Lattice Titanate Pinpoint TemperatureControllerAFM Mechanical&nanotechnology Molybdenum_disulfide conductive Strontium Nanopattern dielectric_trench Ptfe PinpointPFM piezoelectric force microscopy Optical Pipette Step