Development of β-Ga2O3 Thermal Management: A Review

The semiconductor material, beta-phase gallium oxide (β-Ga2O3), is becoming increasingly popular due to its ultrawide bandgap and excellent electrical performance. However, its low thermal conductivity has been proven by first principle calculation with ShengBTE and experimental measurements with time-domain thermos reflectance, and been identified as a significant challenge in the development of next-generation devices. To address the issue, the integration of β-Ga2O3 with high thermally conductive materials can a be good solution. Different simulation packages prove that diamond, AlN, and 4H-SiC can be good candidate materials. To what extent the thermal conductivity of β-Ga2O3 can be improved depends on the integration technique. Ion-cutting technique and fusion bonding technique are effective methods to get high-quality β- Ga2O3/4H-SiC heterostructure which transfers heat more efficiently. β-Ga2O3/4H-SiC SBD and MOSFET based on these techniques show better capability of heat dissipation. Mechanical exfoliation, chemical vapor deposition, and atomic layer deposition are used to create β-Ga2O3/diamond, but more research is necessary to improve the quality of the heterostructure and its thermal conductivity. In terms of β- Ga2O3 devices, vertical device structure is better for dissipating heat, and double-sided cooling strategy is recommended. Besides, β-Ga2O3/metal interfaces affect thermal management as well, and it's found that Cr is suitable for ohmic contact and Ni fits for schottky contact to facilitate the flow of heat. Above all, this review is expected to provide researchers with recent progress in β-Ga2O3 thermal management and inspire more aspiration.