Metal contacts and Schottky barriers at <i>β</i>-Ga2O3 interfaces: High-throughput-assisted first-principles calculations

Abstract

The interfaces formed between metallic electrodes and β-Ga2O3 are crucial components of β-Ga2O3-based electronic and optoelectronic devices. While there have been a few studies on the electrical properties of metal/β-Ga2O3 interfaces, they have been limited to those with a single facet of β-Ga2O3 or a few metals. Here, nine metal/β-Ga2O3 interfaces with the minimum mismatch and interface area are screened from thousands of candidates using the high-throughput interface prediction and generation scheme automatically. The metal contact characteristics of these interfaces are systematically investigated through first-principles calculations. Our calculations demonstrate that the calculated Schottky barrier heights (SBHs) of the metal/β-Ga2O3 interfaces are in accordance with the available experimental results. Among them, Al/β-Ga2O3 (100), Ti/β-Ga2O3 (100), Ni/β-Ga2O3 (100), and Co/β-Ga2O3(2¯01) have relatively low n-type SBHs and high electron transfer efficiency, showing the promise of Al, Ti, Ni, and Co as an ohmic electrode. More importantly, we also obtained several atomic structures of metal/β-Ga2O3 interfaces with promising contact properties, which have not been reported theoretically and experimentally before. These findings lay the groundwork for the rational selection of metal electrode materials and the optimization of device performance in β-Ga2O3 power devices.