Design and research of high voltage β-Ga₂O₃/4H-SiC heterojunction LDMOS

Abstract In recent years, gallium oxide (Ga 2 O 3 ), one of the ultra-wide band-gap semiconductor materials, has been regarded as one of the most promising materials in the field of high-voltage and high-power electronic devices in the future because of its unique electrical properties and low preparation cost. However, it is difficult for β -Ga 2 O 3 materials to form effective P-type doping, so the PN junction is not formed in most of its power devices, which greatly limits the improvement of its voltage resistance. A novel lateral double-diffused metal-oxide-semiconductor field-effect transistor (LDMOS) is proposed to realize a junction β -Ga 2 O 3 power device and improve the voltage resistance performance of β -Ga 2 O 3 power devices. In this device, a β -Ga 2 O 3 power device with a junction is realized by using P-type 4H-SiC to form a PN junction with N-type β -Ga 2 O 3 , and the voltage resistance of the β -Ga 2 O 3 power device is improved. Sentaurus TCAD software was used to simulate the device structure and electrical performance. The device is optimized by adjusting the length of the drift zone, drift zone concentration, SiC channel concentration, and gate oxide thickness. Optimized, the device exhibits a positive threshold voltage of 3.42 V, a breakdown voltage of 2203 V, a specific on-resistance of 7.80 mΩ·cm 2 , and a power figure of merit of 622 MW cm −2 . The results show that the heterojunction device is significant for realizing high-performance junction β -Ga 2 O 3 power devices.