钼圆表面缺陷的形成机理及质量控制

Formation Mechanism of the surface defects on Molybdenum Wafers and their Quality Control

为弄清钼圆表面黑斑和白点的产生原因,采用光学显微镜(OM)和扫描电镜(SEM)对其进行形貌分析,使用能谱仪(EDS)对表面缺陷进行了成分分析,以此为基础,对黑斑和白点的形成分别进行了模拟实验。结果表明,在氢气还原处理后的Mo粉中加入适量Fe/Ni/C和C/SiO_2/CaO粉后,在钼圆表面分别发现了黑斑和白点。这说明Fe-Ni-C和C-O-Mo杂质是造成黑斑和白点的主因。因此,采取必要手段严格控制钼粉原料中Fe/Ni和C/O杂质的含量,是减少和消除黑斑和白点的根本途径。

In order to clarify the wafer formation of black marks and white spots on molybdenum wafer, the analysis of morphology and chemical composition of these defects are performed by using SEM, OM and EDS instruments respectively. Based on the results, the simulation experiments for the forming of black marks and white spots are performed. As a result, the black marks and white spots are found on the surface of molybdenum wafer when adding appropriate amount of Fe/Ni/C and C/SiO 2/CaO powder into hydrogen reduced powder respectively. It demonstrates that the impurity of Fe/Ni/C and C//SiO 2/CaO is the main cause to form black marks and white spots. Therefore, it is the best way to reduce the amount of Fe/Ni and C/O.