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

Yang Dai,Qingsong Ye,Weiwei Zhang,Zhaoyang Lu,Xiaoyi Lei,Chenguang Liao,Han Zhang,Jiangtao Dang,Yunyao Zhang,Yang Li,Wu Zhao

doi:10.3390/mi12080919

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.

Highlights

As one of the main microwave and terahertz wave solid-state sources, impact ionization avalanche transit time (IMPATT) diodes are expected to have broad development prospects in this field due to their better radio frequency (RF) performance [1,2]
Conventional gallium nitride (GaN)-based single-drift region (SDR) IMPATT diodes are mainly composed of the avalanche p-n junction and carrier drift region, but the double-drift region (DDR) diode consists of a p-n junction and two drift regions, and both holes and electrons can be drifted to generate a better RF performance [8,9,10,11]
Avalanche ionization will at the DDR heterojunction interface toelecproduce ode

Summary

Introduction

As one of the main microwave and terahertz wave solid-state sources, impact ionization avalanche transit time (IMPATT) diodes are expected to have broad development prospects in this field due to their better RF performance [1,2]. Conventional GaN-based SDR IMPATT diodes are mainly composed of the avalanche p-n junction and carrier drift region, but the double-drift region (DDR) diode consists of a p-n junction and two drift regions, and both holes and electrons can be drifted to generate a better RF performance [8,9,10,11]. In terms of conventional SDR IMPATT diode, the higher the hole concentration of p-type GaN, the better the RF performance of the diode [12,13]. Because of the overly low p-type region concentration and poor mobility c teristics, the electric field distribution in the avalanche region deviates from the ide uation, deteriorating the impact-ionzation inducing the device p situation, deteriorating the impact-ionzation characteristicscharacteristics and inducing and the device performance to decline. DDR IMPATT device is significantly increased due to the hole participation in the avalancheis significantly increased due to the hole participation in the avalanche-transition pr transition process

Simulation Models and Methods

E GaN materials have obvious

Results and Analysis

Small-Signal Simulation Results and Analysis

Large-Signal

Conclusions