提出了以弱p型(p--GaN)为有源区的p-n结构GaN紫外探测器.由于弱p型层的载流子浓度较低,很容易增加耗尽区的宽度,从而可以增加器件的量子效率.通过模拟计算,研究了金属与p--GaN层的肖特基接触势垒高度、p--GaN层厚度等参数对器件性能的影响.研究结果表明,降低金属与p--GaN层的接触势垒高度、适当减小p--GaN层厚度能够实现有源层方向单一的内建电场,从而提高器件的量子效率.要制备出具有良好性能的p-n结构紫外探测器,必须减小p--GaN层厚度,降低金属与p--GaN层的接触势垒高度.
A new ultraviolet photodetector of employing p menus type GaN(p--GaN)as the active layer is proposed.It is easy to obtain the p--GaN layer with low carrier concentration.As a result,the depletion region can be increased and the quantum efficiency can be improved.The influence of some structure parameters on the performance of the new device is investigated.Through the simulation calculation,it is found that the quantum efficiency increases with the decrease of the barrier height between the metal electrode and the p- -GaN layer, and it is also found that the quantum efficiency can be improved by reducing the thickness of the p- -GaN layer. To fabricate the new photodetector with high performance, we should employ thin p- -GaN layer as the active layer and reduce the Schottky barrier height.