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本文提出了一种严格校准调制光电流相移的方法，在此基础上，采用调制光电流相移分析技术研究了不掺杂氢化非晶硅（a-Si：H）薄膜费米能级以上隙态密度及其分布的光致变化效应．实验发现，光电流相移的校准对确定隙态密度及其分布是至关重要的．除了核准测试系统的相移频率特性外，还需考虑样品本身电阻、电容等参数的影响，否则会使隙态密度偏低1～2个数量级；经严格校准的光电流相移测试，a－Si：H的隙态分布在导带边以下约0．43eV处观察到一个峰，可能是双占据悬挂键D-中心引起的．光照引起浅态减少，深态增加，引起了隙态重新分布．
In this paper, we propose a method to strictly calibrate the phase shift of modulated photocurrent. On the basis of this, the modulation current-phase shift analysis technique is used to study the a-Si: H thin film above the Fermi level Photodiffraction effect of gap density and its distribution. It has been found experimentally that the calibration of photocurrent phase shift is crucial for determining the gap density and its distribution. In addition to verifying the phase-shift frequency characteristics of the test system, the influence of parameters such as the resistance and capacitance of the sample itself must be taken into account. Otherwise, the density of the gap will be reduced by 1 or 2 orders of magnitude. After strictly calibrating the photocurrent phase shift test, Gap distribution of Si: H A peak was observed at about 0.43 eV below the conduction band edge, probably due to the double d-center dangling bond. Light caused by the reduction of shallow, deep state increased, causing the gap redistribution.