Microchannel Flow Cooling for Gallium Oxide Devices

Gallium oxide <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$(\text{Ga}_{2}\mathrm{O}_{3})$</tex> exhibits great potential in power electronic devices due to its ultrawide energy bandgap. However, challenges arise from power devices' inherently low thermal conductivity and self-heating effects. This study proposes a method based on microprocessing of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\text{Ga}_{2}\mathrm{O}_{3}$</tex> substrate to create microchannels at the bottom, promoting thermal dissipation via water/air cooling. Microchannels are formed at the substrate bottom using laser ablation or etching techniques, and water/air flow through these microchannels is employed to reduce substrate temperature. At a thermal source power dissipation of ~ 1.0W under 10V bias voltage, the maximum temperature of untreated <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\text{Ga}_{2}\mathrm{O}_{3}$</tex> substrate reaches <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\sim 250.3^{\circ}\mathrm{C}$</tex>. By utilizing the microchannels with air convection, a decrease of 36% as compared to untreated conditions can be achieved. Meanwhile, adopting microchannel water flow for heat dissipation can reduce the substrate temperature by up to 82.5%. Simulation results demonstrate that dual-channel microchannel water flow cooling is more effective, highlighting its promising application prospects.