基于PID技术的深能级光离化截面测试方法

A New Photoionization Cross Section Measurement Technique Based on PID Control

在分析GaN中深能级中心与入射光子间相互作用的基础上,提出了一种基于PID(proportional-integral-derivative)技术的深能级中心光离化截面的测试方法.在针对分子束外延生长GaN材料的光离化截面测试中,使用该方法得到的测试结果同Klein等人报道的HEMTs器件中光离化谱吻合较好,表明基于PID技术的深能级中心光离化截面测试方法能够精确地测试GaN材料中深能级光离化截面.与现有技术相比,该方法的优点是操作方便、测试相对准确,可作为一种缺陷"指纹"鉴定的新方法应用于GaN材料的深能级研究中.

A new method based on proportional-integral-derivative （PID） control is proposed to measure photoionization cross sec- tions in GaN materials by analysis of release and recaptures carriers of deep centers by incident light. The measurement results of photoionization cross sections on GaN by this method are consistent with the photoionization spectrum in HEMTs reported by Klein. These results indicate that the photoionization cross section technology based on PID control can measure precisely deep level photoi- onization cross sections in GaN material. Compared with existing techniques, this method is more operable and applicable. It can serve as a new ＇fingerprint＇ analysis method in deep level center detection in GaN .