利用二次阳极氧化方法降低N型碲镉汞材料表面复合速度

Reducing the surface recombination velocity of N-HgCdTe by second anodization

利用微波反射光电导衰退法比较了采用一次阳极氧化和二次阳极氧化的N型碲镉汞材料的非平衡载流子寿命及其随温度的变化,通过与理论值进行比较拟合得到了碲镉汞材料表面复合速度随温度的变化曲线.结果发现,二次阳极氧化方法能够更好地降低材料表面悬挂键的密度,同时减少抛光引入的表面缺陷能级的数量,从而降低材料的表面复合速度,改善材料的非平衡载流子寿命,利于制造出高性能的HgCdTe红外探测器.

The lifetime of minority carrier as a function of temperature in n-HgCdTe treated by first anodization and second anodization was measured by μ-PCD and compared. The surface recombination velocity as a function of temperature was simulated from the calculated minority carrier lifetime and measured minority cartier lifetime. The results show that second anodization is an effective way to decrease the density of surface dangling bond and surface defect level, thus reduce the surface recombination velocity and increase the minority carrier lifetime which is beneficial to produce HgCdTe detector with high performance.