基于高频光电导法半导体少数载流子寿命测量系统的设计与实现

Design and Implementation of Semiconductor Minority Carrier Lifetime Measurement System based on High Frequency Photoconductivity Method

基于高频光电导衰减法半导体少数载流子寿命测量基本原理,设计了半导体少子寿命测量系统,并在二极管检波电路的基础上,对信号处理系统进行了改进。该信号处理系统采用反馈式检波电路,相比于传统二极管检波电路,运用运算放大器的反馈原理减小了检波二极管压降产生的误差,同时结合二极管嵌位作用,减小了运算放大器压摆率带来的影响,提高了测量系统的检波能力。通过实验,验证了该检波电路的可行性,测试结果表明,有效提升了测量系统的准确性。

Based on the basic principle of minority carrier lifetime measurement of semiconductor by high frequency photoconductive attenuation method, a minority carrier lifetime measurement system is designed, and the signal processing system is improved on the basis of the diode detection circuit.Compared with the traditional diode detection circuit, the feedback principle of the operational amplifier eliminates the error caused by the voltage drop of the detector diode.At the same time, the effect of the voltage swing rate of the operational amplifier is reduced by the diode embedding effect, which further improves the detection ability of the measurement system.In addition, the feasibility of the detection circuit is verified by experiments, which effectively improves the accuracy of the measurement system.