论文部分内容阅读
通过电化学工作站对p型2英寸(1英寸=2.54 cm)Ge晶圆进行了研究,结合Alpsitec E460抛光机、原子力显微镜(AFM)验证电化学研究对于Ge的化学机械抛光的理论指导意义。结果表明:NaOH作为pH调节剂对Ge具备着比KOH,NH_3·H_2O作为pH调节剂更强的腐蚀性;在H_2O_2浓度一定的条件下,Ge的腐蚀性随着电解液中pH值的增加而增加;在pH相同的条件下,NaClO对Ge的腐蚀性要高于H_2O_2对Ge的腐蚀性。使用Alpsitec E460机台对电化学测试结果进行验证比较,经过条件优化,在5%(质量分数)的SiO_2磨料,1%(原子分数)的H_2O_2,pH=9条件下对Ge晶圆进行化学机械抛光得到Ge的抛光速率为299.87 nm·min~(-1),通过AFM观测抛光120 s后Ge晶圆表面粗糙度RMS=1.86 nm(10μm×10μm),线粗糙度Ra可达0.137 nm。说明了Ge的电化学测试可以有效为实际的CMP研究提供可靠的理论指导。
The p-type 2-inch (1 inch = 2.54 cm) Ge wafers were studied by electrochemical workstation. The Alpsitec E460 polishing machine and atomic force microscope (AFM) were used to verify the theoretical significance of electrochemical studies on Ge chemical mechanical polishing. The results showed that: NaOH as a pH modifier has more corrosive effect on Ge than KOH and NH_3 · H_2O as pH modifiers; under certain H2O2 concentration, the corrosion of Ge increases with the increase of pH in the electrolyte Increase; under the same pH conditions, the corrosion of NaClO to Ge is higher than that of H_2O_2 to Ge. The Alpsitec E460 was used to verify and compare the electrochemical test results. After optimized conditions, the Ge wafer was chemically and mechanically processed with 5% (mass fraction) SiO 2 abrasive, 1% (atomic fraction) H 2 O 2 and pH = 9 The polishing rate of Ge was 299.87 nm · min -1 after polishing. After 120 s AFM observation, the surface roughness of Ge wafer was 1.86 nm (10 μm × 10 μm) and the roughness of Ra was 0.137 nm. It is demonstrated that the electrochemical testing of Ge can provide reliable theoretical guidance for practical CMP research.