Study of p-SiC/n-GaN Hetero-Structural Double-Drift Region IMPATT Diode

Abstract

Nowadays, the immature p-GaN processes cannot meet the manufacturing requirements of GaN impact ionization avalanche transit time (IMPATT) diodes. Against this backdrop, the performance of wide-bandgap p-SiC/n-GaN heterojunction double-drift region (DDR) IMPATT diode is investigated in this paper for the first time. The direct-current (DC) steady-state, small-signal and large-signal characteristics are numerically simulated. The results show that compared with the conventional GaN single-drift region (SDR) IMPATT diode, the performance of the p-SiC/n-GaN DDR IMPATT proposed in this design, such as breakdown voltage, negative conductance, voltage modulation factor, radio frequency (RF) power and DC-RF conversion efficiency have been significantly improved. At the same time, the structure proposed in this design has a larger frequency bandwidth. Due to its greater potential in the RF power density, which is 1.97 MW/cm2 in this study, indicates that the p-SiC/n-GaN heterojunction provides new possibilities for the design and manufacture of IMPATT diode.

Study on Electric Field Modulation and Avalanche Enhancement of SiC/GaN IMPATT Diode

“…As the fabrication process of growing GaN on a SiC substrate is relatively mature [14,15], it can meet the requirements of IMPATT devices. In the literature [16], a p-SiC/n-GaN double drift region IMPATT was proposed, in which electrons and holes are both involved in the transition, so the increase of the injected charge improves the device performance. Compared to the double drift structure, the single drift structure has a smaller size, a simpler structure design, and a higher power output per unit volume.…”