PtfeMembrane Current Writing BreastCancerCell Magnetostrictive kelvin probe force microscopy LiquidCrystal domain_switching CrossSection InorganicCompound Graphite TipBiasMode SKKU Pore biocompatible DataStorage Piezoelectric PDMS Nickel Force-distance Scratch Conductive AFM HardDisk Electronics Implant Layer NusEce ContactModeDots Chromium Film Silver cross section Sio2 HOPG IRDetector