Thermal properties of Ga2O3 thin films and devices prepared on sapphire and SiC substrates by liquid-injection MOCVD
At a Glance
Section titled āAt a Glanceā| Metadata | Details |
|---|---|
| Publication Date | 2024-03-15 |
| Authors | Filip Gucmann, M. Ťapajna, K. HuÅ”ekovĆ”, Edmund DobroÄka, A. RosovĆ” |
| Institutions | University of Bristol, Wuhan University |
Abstract
Section titled āAbstractāGallium oxide (Ga<sub>2</sub>O<sub>3</sub>) is a promising ultra-wide bandgap (UWBG) semiconductor that was quickly recognised as a suitable material for fabrication of optoelectronic devices or high-power rectifiers and switches, potentially greatly exceeding the capabilities of mainstream Si, GaN, and SiC. Despite many advantageous material properties, large-area bulk Ga<sub>2</sub>O<sub>3</sub> substrates remain expensive, and Ga<sub>2</sub>O<sub>3</sub> itself suffers from low lattice thermal conductivity - crucial for an efficient heat extraction from the active device area, generated by Joule losses during the on-state operating conditions. Heteroepitaxy of Ga<sub>2</sub>O<sub>3</sub> films offers a possible route for a low-cost production of Ga<sub>2</sub>O<sub>3</sub>-based power or optoelectronic devices if e.g. sapphire substrates are used, or much improved thermal performance if highly-thermally-conductive substrates such as SiC or polycrystalline diamond are used. In this work we use liquid-injection metalorganic chemical vapour deposition (LI-MOCVD) to grow thin Ga<sub>2</sub>O<sub>3</sub> films on sapphire and 4H-SiC and to fabricate depletion-mode metal-oxide-semiconductor field-effect transistors (MOSFETs). Structural and transport properties of the Ga<sub>2</sub>O<sub>3</sub> films and devices prepared on both substrates are analysed. Then, thermal properties of grown Ga<sub>2</sub>O<sub>3</sub> films, and Ga<sub>2</sub>O<sub>3</sub>/SiC and Ga<sub>2</sub>O<sub>3</sub>/sapphire interfaces are presented and implications for Ga<sub>2</sub>O<sub>3</sub>-based devices are outlined.