碲锌镉晶体化学机械抛光液的研究_敖孟寒
第39卷 第1期 红 外 技 术 V ol.39 No.1 2017年1月 Infrared Technology Jan. 2017 〈材料与器件〉
碲锌镉晶体化学机械抛光液的研究
敖孟寒1,2，朱丽慧1，孙士文2
（1. 上海大学材料科学与工程学院，上海 200072；2. 中国科学院红外成像材料与器件重点实验室，上海 200083）
摘要：本文以硅溶胶为磨料颗粒、次氯酸钠（NaClO ）为氧化剂制备适用于CZT 晶片的化学机械抛光液。采用XPS 能谱分析CZT 表面元素化学态，研究CZT 化学机械抛光过程中抛光液的化学作用机理，使用激光干涉仪、原子力显微镜研究抛光液中NaClO 含量对晶片抛光速率、晶片表面PV 值及表面粗糙度Ra 的影响。结果表明，硅溶胶-次氯酸钠抛光液通过与CZT 晶体中Te 单质或CdTe 发生化学反应，生成TeO 2。随后在一定压力下，抛光盘与CZT 晶片发生相对运动，并在硅溶胶磨料颗粒的辅助作用下去除反应物。当NaClO 含量在2%～10%时，随着NaClO 含量的增加，晶片表面PV 值和粗糙度Ra 值先降低后升高，去除速率则随着NaClO 含量的增加而增加。NaClO 含量为6%时，PV 值和Ra 值最低，得到的晶片表面质量最好。
关键词：化学机械抛光；CZT 晶体；粗糙度；平整度
中图分类号：TN304 文献标识码：A 文章编号：1001-8891(2017)01-0022-05
Research on Chemical-mechanical Polishing Slurry for CdZnTe Crystal
AO Menghan1,2，ZHU Lihui1，SUN Shiwen2
(1. School of Materials Science & Engineering, Shanghai University, Shanghai 200072, China;
2. Key Laboratory of Infrared Imaging Materials and Detectors, Chinese Academy of Science, Shanghai 200083, China)
Abstract ：In this paper, silica solution and NaClO were chosen as raw materials to prepare chemical-mechanical polishing slurry for CdZnTe crystal. The mechanism of chemical-mechanical polishing slurry to CZT was researched by analyzing the elemental state of the CZT surface with X-ray Photoelectron Spectrometer (XPS). Laser Interferometer and Atomic Force Microscope (AFM) were used to investigate the effect of NaClO content on polishing rate, surface flatness and roughness. The results show that the chemical-mechanical polishing slurry mainly reacts with Te or CdTe, and TeO2 is obtained. Then at a certain pressure, there is relative motion between polishing discs and CZT wafer, and the reaction film is removed under a supporting role of SiO2 particles, which make the surface become smooth. When the NaClO content ranges from 2% to 10%, with the increase of NaClO, the PV value and roughness of CZT surface decrease at first and then increase, while the polishing rate increases all the time. When the NaClO content is 6%, the PV value and roughness reach the minimum, and the polishing surface of CdZnTe with high quality is obtained.
Key words：chemical-mechanical polishing，CZT crystal，roughness ，flatness
探测器的质量，所以获得高质量的CZT 抛光表面非0 引言 常重要。
碲锌镉（CZT ）晶体常作为HgCdTe 生长的衬底国内对CZT 晶体表面处理使用较多的工艺是机材料以及生产核辐射探测器的理想材料[1]。CZT 晶片械研磨、机械抛光和化学腐蚀[2]。国外文献曾提及化的表面粗糙层、划痕等缺陷会严重影响所生长材料和学机械抛光技术可用于CZT 晶体的表面处理，但对
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