Optimization of CuO/GaO Heterojunction Diodes for High-Voltage Power Electronics.

This study optimizes the CuO/GaO heterojunction diodes (HJDs) by tailoring the structural parameters of CuO layers. The hole concentration in the sputtered CuO was precisely controlled by adjusting the Ar/O gas ratio. Experimental investigations and TCAD simulations were employed to systematically evaluate the impact of the CuO layer dimension and hole concentration on the electrical performance of HJDs. The results indicate that increasing the diameter dimension of the CuO layer or tuning the hole concentration to optimal values significantly enhances the breakdown voltage (V) of single-layer HJDs by mitigating the electric field crowing effects. Additionally, a double-layer CuO structure (p CuO/p CuO) was designed and optimized to achieve an ideal balance between the V and specific on-resistance (R). This double-layer HJD demonstrated a high V of 2780 V and a low R of 6.46 mΩ·cm, further yielding a power figure of merit of 1.2 GW/cm. These findings present a promising strategy for advancing the performance of GaO devices in power electronics applications.