摘要
通过比较微量铜铁单独存在和共存时对p -型硅片表面的污染,采用电化学直流极化和交流阻抗技术以及SEM、EDX和AES等现代表面分析技术,对未污染和受污染的硅片表面进行了初步的研究.结果表明,当氢氟酸溶液中同时含有ppb 水平(10-9)的铜铁杂质时,不但铜会沉积在硅片表面上发生铜污染,而且还导致硅片表面的碳污染,并从电化学极化电阻、元素深度分布和空间电荷效应等方面对硅片表面铜与碳污染进行了初步的分析和讨论.
Through a comparison of surface contamination of p-type silicon wafer by trace amounts of copper and iron when they are present in solutions separately or simultaneously,a preliminary study is conducted to investigate the non-contaminated or contaminated silicon wafer by employing electrochemical DC polarization and AC impedance techniques,as well as modern surface analysis technologies including SEM,EDX,and AES.It is revealed that in hydrofluoric acid solutions containing both ppb-level of copper and iron,not only would copper deposition take place,but also could carbon contamination occur at the wafer surface.General analysis and discussion in copper and carbon contamination are provided based on the polarization resistance,elemental depth distribution,and space charge effect.
基金
国家自然科学基金资助项目(批准号:20073036)~~
关键词
硅片清洗
金属污染
铜沉积
碳污染
wafer cleaning
metallic contamination
copper deposition
carbon contamination
