Study on self heating effect of enhancement-mode Ga<sub>2</sub>O<sub>3</sub> vertical MOSFET

Abstract

<p indent="0mm">In this paper, a vertical enhanced Ga₂O₃ MOSFET is designed. Due to the low thermal conductivity of gallium oxide material, the output characteristics of the device under different crystal orientation materials, different thermal resistance and different temperature are studied. The thermal characteristics of Ga₂O₃ MOSFET are analyzed based on the temperature distribution characteristics of the device. The thermal conductivity model studies the effect of different orientation of gallium oxide on the output characteristics and temperature distribution of the device, and it is found that the thermal conductivity of [010] orientation is the best. When <italic>T</italic>=<sc>300 K,</sc> the thermal conductivity is about <sc>0.1 W/cm K,</sc> which is higher than that of other crystal directions, and the corresponding output saturation current is the largest under the same voltage (<italic>V</italic>_gs=<sc>3 V, </sc><italic>I</italic>_dsat&gt;<sc>400 A/cm²).</sc> Furthermore, the output characteristic curves of different crystal directions under different temperature and different thermal resistance are studied. With the decrease of thermal resistance, the heat dissipation capacity at the device boundary is improved. Thus, the influence of self-heating effect is suppressed and the drain saturation current increases. The normal operation of the device can be ensured when the boundary thermal resistance is <sc>0.01–0.005 cm² K/W.</sc> All of these provide reliable methods and reference value for optimizing device performance in the future.