Friction frequency_modulation CBD PetruPoni_Institute ContactModeDots Tungsten_disulfide SFAs Chemical Vapor Deposition Flake InLiquid HiVacuum MoirePattern Conductivity Adhesive SKKU PtfeMembrane Polyimide Electrical&Electronics Chloroform HanyangUniv mono_layer molecular_beam Hexatriacontane molecular_self_assembly LifeScience Composition FrictionalForce Ferroelectric Magnets silicon_oxide Cobalt PFM Optoelectonics bias_mode CaMnO3