碲镉汞衬底上沉积类金刚石薄膜的界面分析

INTERFACE ANALYSIS OF DLC FILM DEPOSITED ON Hg_(1-x)Cd_xTe

采用等离子增强化学气相法 (PECVD)在碲镉汞 (MCT)衬底上沉积纳米颗粒的类金刚石薄膜 (DLC) ,对DLC MCT界面进行了俄歇电子能谱 (AES)分析 ,并与离子溅射法 (IS)沉积的ZnS MCT界面比较 ,结果表明DLC和ZnS薄膜都能较好地抑制MCT中HgTe的分解 ,在一定程度上阻挡了MCT中Hg的外扩散 .相对于ZnS中的S而言 ,DLC的C在MCT中的内扩散深度较小 (前者为 4 0 0 ,而后者仅为 2 0 0 ) .

A dense and homogeneous nanograins diamond-like carbon (DLC) film was deposited on the well-polished HgCdTe wafer by radio frequency plasma chemical vapor deposition at room temperature. The interface of DLC/HgCdTe was studied by AES and compared with that of ZnS/HgCdTe, which was prepared by ion sputtering( IS). The result shows that both DLC film and ZnS film can suppress the dissociation of the weak bonding HgTe, and prevent Hg escaping from MCT surface to some extent. However, both Zn and S in ZnS layer tend to diffuse inward MCT, while diffusion of C from DLC layer into MCT is rather slight. In particular, IR transmission of MCT deposited with DLC is remarkable raised comparing to the naked surface and higher than that of MCT deposited with ZnS.