A Novel Structure To Enable Low Local Electric Field And High On-State Current In Gan Photoconductive Semiconductor Switches

The use of GaN photoconductive semiconductor switches (PCSSs) is plugged by the high local electric field at the electrode edges and the low on-state current in the sub-bandgap triggering mode. Therefore, a new highpower semi-insulating GaN PCSS structure, which is a quantum well coupled with a trench PCSS (QWTPCSS), is presented. The trench changes the electric field distribution. In the off state, the maximum electric field of the GaN QWTPCSS is 202.1 kV cm(-1), which is 60.57% lower than the 512.6 kV cm(-1) of the conventional structure. Moreover, the introduced AlGaN layer forms two-dimensional electron gases (2DEGs) in the conduction state; when triggered by a 532 nm laser, such 2DEGs contribute to the on-state current, which increases by 9.37% relative to that of the structure without AlGaN. These results demonstrate the potential of QWTPCSS to achieve high power.