Polyimide self-assembled_monolayer SThM Biology University_of_Regensburg HafniumDioxide LiquidCell ScanningIon-ConductanceMicroscopy IIT-chennai cross section GlassTemp Phosphide FuelCell Composition SiWafer DIWafer HumanHair LifeScience semifluorinated_alkane ThermalDetectors Implant Aluminium_Oxide I-VSpectroscopy Croatia Pores EPFL ElectrostaticForceMicroscopy tip_bias_mode Self-assembledMonolayer CrossSection semifluorinated alkane Sapphire Insulator Lattice MESA structure