【International Papers】Schottky barrier heights and electronic transport in Ga₂O₃ schottky diodes

      Researchers from the Kwangwoon University have published a dissertation titled " Schottky barrier heights and electronic transport in Ga₂O₃ schottky diodes " in IOP Science.

Abstract

      Schottky contact, which is formed at the interface between a metal and a semiconductor, plays a pivotal role in the electrical properties of Schottky barrier diodes (SBDs). Schottky contact has not been widely investigated in heterostructural SBDs employing gallium oxide (Ga₂O₃), despite heterostructure being closely related to poor thermal conductivity. To make up for poor thermal conductivity of Ga₂O₃, it is reported that heterostructure with 4H-SiC which has high thermal conductivity is good strategy. Herein, we studied the carrier-transport mechanisms and electrical characteristics of Ga₂O₃ SBDs employing pre-treated Ga₂O₃ thin films and various Schottky metals. For analysis, thermionic emission and thermionic field emission (TFE) models were used. A comparison of the Schottky barrier heights (SBHs) and ideality factors obtained using these models indicated that the dominant carrier-transport mechanism in pre-treated Ga₂O₃ SBDs is TFE. The values of SBHs determined using current–voltage and capacitance–voltage characteristics and X-ray photoelectron spectroscopy depend on the interface quality, as with inhomogeneous SBH. The SBHs of SBDs pre-treated via annealing at 900 ℃ under an N₂ atmosphere were lower than those of untreated SBDs. Furthermore, SBDs employing Ni as the anode material exhibited lower SBHs than those employing Au. Thus, the use of annealing pre-treatments and anode metals with low work functions has significant potential for reducing the Schottky barrier heights in Schottky diodes and improving their electric properties.

Paper Link：https://doi.org/10.1088/2053-1591/ace0a4