摘要
主要从理论上研究脉冲光信号激励对少数载流子寿命测试结果的影响.通过研究两种理想的脉冲光源——高斯脉冲、方脉冲与理想δ函数光源产生的光电导衰减曲线的对比,发现对于高斯脉冲光源,只有在脉宽的条件下才可等效于δ函数光源;而脉宽的方脉冲才能等效为δ函数光源.否则脉冲光过长的脉宽和下降沿将对光电导衰减曲线中进一步分离出的表面复合速度和少子体寿命结果造成误差.若样品受表面状况影响较小时(如体寿命较低或表面复合速度低时),则可对两种理想脉冲光源的要求适当放宽.
The influence of pulse laser stimulation on minority carrier lifetime measurement is theoretically analyzed. By comparing the photoconductive decay curves induced by ideal Gaussian pulse and the square pulse, with that induced by an g-function illumination, it is found that the Gaussian pulse light source with less than 2ns pulse width or the square pulse light source with less than 10ns pulse width can be equivalent to an δ illumination. Otherwise, wide pulse and slow falling edge can cause the errors of surface recombination velocities and bulk lifetime extracted from the photoconductive decay curve. For the samples less influenced by the surface conditions （for example, shorter bulk lifetime or lower surface recombination velocities）, the requirement of pulse width can be not strict.
出处
《测试技术学报》
2007年第5期400-404,共5页
Journal of Test and Measurement Technology
关键词
脉冲光
少子寿命
高斯脉冲
方脉冲
表面复合
pulse illumination
minority carrier lifetime
Gaussian pulse
square pulse
surface recombination
