320 nm AlGaN肖特基型紫外探测器的研制

Fabrication of 320 nm AlGaN Based Schottky Ultraviolet Detector

制备了i-AlGaN/n-AlGaN肖特基结构的背照射AlGaN紫外光电探测器,并进行了光电性能的研究。室温下发现光电探测器的截止波长为320 nm,但在350~400 nm之间存在宽广的深能级响应。通过对探测器进行电流-电压和电容-电压的测试,分析了350~400 nm之间深能级响应谱出现的原因。电流-电压测试结果表明理想因子在2以上,说明正向输运机制中存在由缺陷能级引起的复合电流,电容平方倒数对电压斜率的变化表明在该探测器本征层中存在由缺陷引起的深能级响应。两种测试分析结果均表明该响应由本征层中的缺陷引起。

An i-AlGaN/n-AlGaN Schottky structure based back-illuminated AlGaN ultraviolet photodetector is fabricated and its photoelectric properties are investigated.At room temperature,the cut-off wavelength of photodetectors is found at 320 nm,but there is a broad deep level response between 350~400 nm.The current voltage and capacitance voltage are tested.The ideal factor is above 2 which indicate that the composite current caused by the defect level exist in the positive transport mechanism.The change of reciprocal of capacitance square-voltage slope indicate that response of deep level caused by defects exist in the detector intrinsic layer.The results shown the reason of deep level response.It is induced by the defect in the intrinsic layer.