Development of Ga2O3 Based Structures for High Power Applications

North Carolina State University, Raleigh NC

Investigators

Abstract

Non-Technical Description: In the past decade, wide-bandgap semiconductor materials such as GaN have enabled a variety of optoelectronic and electronic technologies by providing new capabilities at elevated temperatures and high voltages. This research project focuses on investigating the growth and fundamental properties of gallium oxide (Ga2O3), a material that has not been extensively explored for electronics. The knowledge gained in this study leads to high-quality gallium oxide materials with a low defect density and controllable electronic properties for high-power devices. The project topic increases public awareness of the importance of novel materials for energy-efficient power electronics, essential to our future quality of life. In addition, graduate and undergraduate students are trained in materials science research, with a special emphasis on involving underrepresented groups. The project also fosters interdisciplinary collaborations at local, national and international levels and transforms fundamental materials research findings to industry. Technical Description: The scientific objective of this project is to establish the relationship between the thin-film growth and the structural and physical properties of Ga2O3. The Ga2O3 thin films are deposited using three complimentary growth techniques including pulsed laser deposition, pulsed electron deposition and metalorganic vapor phase deposition with the ultimate goal to explore its potential for power electronics. The research explores: (i) the optimum growth conditions of beta-Ga2O3 through homoepitaxy and heteroepitaxy; (ii) interface strategies for defect reduction; (iii) doping options (e.g., Si, Sn and Mg) for high incorporation efficiency and enhanced conductivities; (iv) annealing procedures for improving the structural and electrical properties; and (v) in-plane anisotropy and its effects on electrical and thermal transport properties. The study provides a fundamental understanding of the roles of defects and dopants on the overall structural and electrical properties in this wide bandgap material.