p-Type Field Effect Transistors Based on Schottky Junction Ag@SnO Nanostructures

Tin monoxide (SnO) is a p-type semiconductor which is promising in field effect transistors (FETs) applications. However, nanostructure SnO has hardly been applied in FETs due to its stability issue. Herein, oleylamine protected Ag@SnO core–shell nanostructures have been synthesized by a hydrothermal method and configured as FETs. X-ray diffraction, Raman spectroscopy and X-ray photoelectron spectroscopy measurements are carried out to confirm the formation of pure phase SnO. The Ag@SnO core–shell single nanostructure FETs and thin film transistors are successfully fabricated on Si/SiO2 substrates. The doping of Ag in SnO and the formation of Schottky junction between SnO and Ag effectively improve the performance of FETs. The Ag nanowire (NW) core provides the unhindered carrier transport route, and the Schottky junction formed between Ag NW and SnO effectively constrains the leakage current. The nanostructure FETs show typical p-type characteristics with a premium on/off ratio (Ion/Ioff) of 3.3 × 105, a subthreshold swing of 0.09 V dec–1 and a high p-type field effect mobility (μFE) of 1.93 cm2 V –1 s –1. The excellent properties of Ag@SnO NWs FETs promise to be important for the next-generation p-type FETs.