SILICON NANOWIRE TRANSISTOR FABRICATED BY AFM NANOLITHOGRAPHY FOLLOWED BY WET CHEMICAL ETCHING PROCESS

Abstract

Atomic force microscope (AFM) nanolithography was performed to create nanowire transistor pattern via local anodic oxidation process on surface of silicon-on-insulator (SOI) wafer. This nanoscale oxide pattern is used as a mask system for chemical etching to produce silicon nanowire transistor. The device with component structures of a silicon nanowire (SiNW) as channel with source, drain, and gate pads had been drawn at 9 V tip voltage, 6 μm/s writing speed with humidity 55.8–68.9%RH. The designed device was etched with tetramethylammonium hydroxide (TMAH) to remove uncovered silicon layer but oxide pattern remains. In order to obtain SiNW transistor, sample was etched using hydrogen fluoride (HF) to remove oxide layer. From the AFM and field emission scanning electron microscope (FESEM) observation found that the SiNW transistor with wire size of 92.65 nm in wire thickness, 90.83 nm wire width and 10.30 μm in length with contact pads size of about 5 μ m × 5 μ m has been successfully fabricated.