Electrothermal Analysis for Layout Design of Hetero-Integrated β-Ga₂O₃ SBDs on SiC

<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\beta $ </tex-math></inline-formula>-phase gallium oxide (<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\beta $ </tex-math></inline-formula>-Ga2O3) holds promise for next-generation power electronics, but its low thermal conductivity calls for effective thermal management, especially in high-power applications. Previous research mainly focused on using high thermal conductivity substrate strategies to enhance the heat dissipation of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\beta $ </tex-math></inline-formula>-Ga2O3 devices. This work optimizes the electrode layouts (including shape, size, and gap) of hetero-integrated <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\beta $ </tex-math></inline-formula>-Ga2O3 Schottky barrier diodes (SBDs) on SiC through comprehensive analysis using 3-D Raman thermometry and electrothermal simulations. Peak temperature occurs near the inner electrode in circular electrode SBDs and near the anode in interdigital electrode SBDs due to the higher current density. In particular, interdigital electrodes provide a more uniform contact area than circular electrodes, promoting better heat dissipation, but an abrupt temperature rise occurs at the finger anode tip due to current crowding. A strategy of balancing electrical and thermal characteristics is implemented to comprehensively evaluate the performance of power devices. Results show that widening the electrode gap (GE) and chamfering the electrode tip can promote heat dissipation and reduce the peak temperature, while largely maintaining the electrical performance (such as <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${I}_{\text {ON}}$ </tex-math></inline-formula>/<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${I}_{\text {OFF}}$ </tex-math></inline-formula> ratio, subthreshold swing, ideality factor, and ON-state resistance). Our work benefits the scientific community by quantitatively analyzing the electrode layout to optimize electrothermal performance of hetero-integrated <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\beta $ </tex-math></inline-formula>-Ga2O3 SBDs and providing 3-D thermal analysis to visualize device-level heat dissipation.