Fabrication and electrical characterization of nanoscaled-schottky diodes based on metal suicide/silicon nanowires with scanning probe lithography and wet etching

Nanometer-sized Schottky diodes based on nickel monosilicide (NiSi)/silicon nanowire (SiNW) heterojunction have been fabricated and studied for their electrical transport characteristics. The SiNW was fabricated by scanning probe lithography (SPL) and tetramethylammonium (TMAH) wet etching. The diameter and height of the SiNWs were 60 and 25 nm, respectively. A Schottky barrier diode was obtained by patterning nickel film onto half of the SiNW by conventional lithography, and then forming nickel monosilicide by the solid state reaction between nickel and silicon under rapid thermal annealing (RTA) in N₂ ambient for 1 min. The current-voltage characteristics measured exhibited clear rectifying behavior consistent with a 0.22 eV schottky barrier height, and no reverse bias breakdown was observed up to a voltage of -5 V.