A novel compound cleaning solution for benzotriazole removal after copper CMP  

作　　者：顾张冰 刘玉岭 高宝红 王辰伟 邓海文 

机构地区：[1]Institute of Microelectronics,Hebei University of Technology

出　　处：《Journal of Semiconductors》2015年第10期155-160,共6页半导体学报（英文版）

基　　金：Project supported by the Special Project Items No.2 in National Long-Term Technology Development Plan,China(Nos.2009ZX02308-003,2014ZX02301003-007)

摘　　要：After the chemical mechanical planarization （CMP） process, the copper surface is contaminated by a mass of particles （e.g. silica） and organic residues （e.g. benzotriazole）, which could do great harm to the integrated circuit, so post-CMP cleaning is essential. In particular, benzotriazole （BTA） forms a layer of Cu-BTA film with copper on the surface, which leads to a hydrophobic surface of copper. So an effective cleaning solution is needed to remove BTA from the copper surface. In this work, a new compound cleaning solution is designed to solve two major problems caused by BTA： one is removing BTA and the other is copper surface corrosion that is caused by the cleaning solution. The cleaning solution is formed of alkaline chelating agent （FA/O II type）, which is used to remove BTA, and a surfactant （FA/O I type）, which is used as a corrosion inhibitor. BTA removal is characterized by contact angle measurements and electrochemical techniques. The inhibiting corrosion ability of the surfactant is also characterized by electrochemical techniques. The proposed compound cleaning solution shows advantages in removing BTA without corroding the copper surface.After the chemical mechanical planarization （CMP） process, the copper surface is contaminated by a mass of particles （e.g. silica） and organic residues （e.g. benzotriazole）, which could do great harm to the integrated circuit, so post-CMP cleaning is essential. In particular, benzotriazole （BTA） forms a layer of Cu-BTA film with copper on the surface, which leads to a hydrophobic surface of copper. So an effective cleaning solution is needed to remove BTA from the copper surface. In this work, a new compound cleaning solution is designed to solve two major problems caused by BTA： one is removing BTA and the other is copper surface corrosion that is caused by the cleaning solution. The cleaning solution is formed of alkaline chelating agent （FA/O II type）, which is used to remove BTA, and a surfactant （FA/O I type）, which is used as a corrosion inhibitor. BTA removal is characterized by contact angle measurements and electrochemical techniques. The inhibiting corrosion ability of the surfactant is also characterized by electrochemical techniques. The proposed compound cleaning solution shows advantages in removing BTA without corroding the copper surface.

关 键 词：benzotriazole removal alkaline chelating agent SURFACTANT corrosion inhibitor 

分 类 号：TG178[金属学及工艺—金属表面处理]