The cleaning of copper interconnects after chemical mechanical planarization （CMP） process is a crit- ical step in integrated circuits （ICs） fabrication. Benzotriazole （BTA）, which is used as corrosion inhibitor...The cleaning of copper interconnects after chemical mechanical planarization （CMP） process is a crit- ical step in integrated circuits （ICs） fabrication. Benzotriazole （BTA）, which is used as corrosion inhibitor in the copper CMP slurry, is the primary source for the formation of organic contaminants. The presence of BTA can degrade the electrical properties and reliability of ICs which needs to be removed by using an effective cleaning solution. In this paper, an alkaline cleaning solution was proposed. The alkaline cleaning solution studied in this work consists of a chelating agent and a nonionic surfactant. The removal of BTA was characterized by contact angle measurements and potentiodynamic polarization studies. The cleaning properties of the proposed cleaning solution on a 300 mm copper patterned wafer were also quantified, total defect counts after cleaning was studied, scanning electron microscopy （SEM） review was used to identify types of BTA to confirm the ability of cleaning solution for BTA removal. All the results reveal that the chelating agent can effectively remove the BTA residual, nonionic surfactant can further improve the performance.展开更多
This work investigates systematically the effect of FA/O II chelating agent and FA/O I surfactant in alkaline cleaning solutions on benzotriazole （BTA） removal during post-Cu CMP cleaning in GLSI under the con- diti...This work investigates systematically the effect of FA/O II chelating agent and FA/O I surfactant in alkaline cleaning solutions on benzotriazole （BTA） removal during post-Cu CMP cleaning in GLSI under the con- dition of static etching. The best detergent formulation for BTA removal can be determined by optimization of the experiments of single factor and compound cleaning solution, which has been further confirmed experimentally by contact angle （CA） measurements. The resulting solution with the best formulation has been measured for the actual production line, and the results demonstrate that the obtained cleaning solution can effectively and efficiently remove BTA, CuO and abrasive SiO2 without basically causing interfacial corrosion. This work demonstrates the possibility of developing a simple, low-cost and environmentally-friendly cleaning solution to effectively solve the issues of BTA removal on post-Cu CMP cleaning in a multi-layered copper wafer.展开更多
基金supported by the Natural Science Foundation of Hebei Province,China(No.F2015202267)the Scientific Innovation Grant for Excellent Young Scientists of Hebei University of Technology(No.2015007)
文摘The cleaning of copper interconnects after chemical mechanical planarization （CMP） process is a crit- ical step in integrated circuits （ICs） fabrication. Benzotriazole （BTA）, which is used as corrosion inhibitor in the copper CMP slurry, is the primary source for the formation of organic contaminants. The presence of BTA can degrade the electrical properties and reliability of ICs which needs to be removed by using an effective cleaning solution. In this paper, an alkaline cleaning solution was proposed. The alkaline cleaning solution studied in this work consists of a chelating agent and a nonionic surfactant. The removal of BTA was characterized by contact angle measurements and potentiodynamic polarization studies. The cleaning properties of the proposed cleaning solution on a 300 mm copper patterned wafer were also quantified, total defect counts after cleaning was studied, scanning electron microscopy （SEM） review was used to identify types of BTA to confirm the ability of cleaning solution for BTA removal. All the results reveal that the chelating agent can effectively remove the BTA residual, nonionic surfactant can further improve the performance.
基金Project supported by the Major National Science and Technology Special Projects(No.2009ZX02308)
文摘This work investigates systematically the effect of FA/O II chelating agent and FA/O I surfactant in alkaline cleaning solutions on benzotriazole （BTA） removal during post-Cu CMP cleaning in GLSI under the con- dition of static etching. The best detergent formulation for BTA removal can be determined by optimization of the experiments of single factor and compound cleaning solution, which has been further confirmed experimentally by contact angle （CA） measurements. The resulting solution with the best formulation has been measured for the actual production line, and the results demonstrate that the obtained cleaning solution can effectively and efficiently remove BTA, CuO and abrasive SiO2 without basically causing interfacial corrosion. This work demonstrates the possibility of developing a simple, low-cost and environmentally-friendly cleaning solution to effectively solve the issues of BTA removal on post-Cu CMP cleaning in a multi-layered copper wafer.
