A simulation study of field plate termination in Ga 2 O 3 Schottky barrier diodes

In this work, the field plate termination is studied for Ga 2 O 3 Schottky barrier diodes (SBDs) by simulation. The influence of field plate overlap, dielectric material and thickness on the termination electric field distribution are demonstrated. It is found that the optimal thickness increases with reverse bias increasing for all the three dielectrics of SiO 2 , Al 2 O 3 , and HfO 2 . As the thickness increases, the maximum electric field intensity decreases in SiO 2 and Al 2 O 3 , but increases in HfO 2 . Furthermore, it is found that SiO 2 and HfO 2 are suitable for the 600 V rate Ga 2 O 3 SBD, and Al 2 O 3 is suitable for both 600 V and 1200 V rate Ga 2 O 3 SBD. In addition, the comparison of Ga 2 O 3 SBDs between the SiC and GaN counterpart reveals that for Ga 2 O 3 , the breakdown voltage bottleneck is the dielectric. While, for SiC and GaN, the bottleneck is mainly the semiconductor itself.