PN结分别制备在HgCdTe外延薄膜材料的Cd组分非线性分布区和线性分布区的高组分端，研究了具有组分梯度的HgCdTe探测器的光电特性。计算不同温度下组分梯度产生的内建电场，结果显示Cd组分线性分布产生的内建电场在100～200 V/cm，而Cd组分非线性分布使得样品表面薄层的内建电场高达2 000 V/cm，推测组分梯度产生的内建电场对光生少子运动的影响是引起两个样品光电性能差异的主要原因。通过分析样品响应率随温度的三种不同变化趋势，提出利用温度调控组分梯度产生的内建电场，有利于降低空间电荷效应，为大注入下提高HgCdTe探测器的饱和阈值提供了一种新的设计思路。

The junctions are prepared at the high composition end of nonlinear composition region and linear composition region respectively, and the photoelectric performance of HgCdTe detector with composition gradient was studied. By calculating the built-in electric field of composition gradient in two samples with different temperatures, the results show that the built-in electric field generated by the linear composition distribution is 100 ~ 200 V/cm, while the built-in electric field generated by the nonlinear composition distribution makes the electric field on surface of the sample as high as 2 000 V/cm. The analysis indicates that the influence of the built-in electric field generated by the composition gradient on the movement of the minority carrier is the main reason for the difference in the photoelectric properties of the two samples. By analyzing the three different trends of responsivity of the sample with different temperatures, it is proposed that using the built-in electric field generated by the composition gradient which is controlled by temperature can reduce the space charge effect and provides a new thought for improving the saturation threshold of the HgCdTe detector under large injection.