Packaged Ga<inf>2</inf>O<inf>3</inf>Schottky Rectifiers with over 60-A Surge Current Capability

Abstract

Ultrawide-bandgap gallium oxide (Ga2O3) devices have recently emerged as promising candidates for power electronics; however, the low thermal conductivity (kT) of Ga2O3 causes serious concerns about their electrothermal ruggedness. This letter presents the first experimental demonstrations of large-area Ga2O3 Schottky barrier diodes (SBDs) packaged in the bottom-side-cooling and double-side-cooling configurations, and for the first time, characterizes the surge current capabilities of these packaged Ga2O3 SBDs. Contrary to popular belief, Ga2O3 SBDs with proper packaging show high surge current capabilities. The double-side-cooled Ga2O3 SBDs with a 3 × 3-mm2 Schottky contact area can sustain a peak surge current over 60 A, with a ratio between the peak surge current and the rated current superior to that of similarly-rated commercial SiC SBDs. The key enabling mechanisms for this high surge current are the small temperature dependence of on-resistance, which strongly reduces the thermal runaway, and the double-side-cooled packaging, in which the heat is extracted directly from the Schottky junction and does not need to go through the low-kT bulk Ga2O3 chip. These results remove some crucial concerns regarding the electrothermal ruggedness of Ga2O3 power devices and manifest the significance of their die-level thermal management.