分子束外延的CdTe在碲镉汞中波器件中钝化效果

The passivation effects of CdTe deposited by MBE in MW HgCdTe photodiodes

采用分子束外延技术(MBE)制备了碲化镉(CdTe)原位钝化的中波碲镉汞(HgCdTe)材料。原子力显微镜(AFM)和扫描电子显微镜(SEM)测试结果表明,分子束原位外延的CdTe可见cross-hatch,表面粗糙度为1~2 nm,CdTe和HgCdTe界面结合紧密。微波光导测试结果显示,77 K时,与表面处理后非原位CdTe钝化的HgCdTe材料相比,CdTe原位钝化的HgCdTe材料的少子寿命较大。制备了分子束外延CdTe原位钝化的中波HgCdTe光伏器件,和相同材料上的非原位CdTe/ZnS双层钝化制备的器件I-V特性相似。

The characterizations of CdTe film deposited by molecular beam epitaxy(MBE)in-suit had been studied using atomic force microscopy(AFM)and scanning electron microscopy(SEM). The cross-hatch pattern can be seen on the CdTe film surface. The roughness of CdTe film deposited by MBE in-suit on HgCdTe is about 1~2 nm. The minority carrier lifetime of HgCdTe passivated by CdTe in-suit is larger than the HgCdTe passivated by the CdTe deposited by E-beam evaporation after etched top 1um HgCdTe at 77 K. The I-V characteristics of MW photodiodes passivated by the CdTe in-suit are similar with the photodiodes passivated by the CdTe/ZnS films.