复配表面活性剂对铜CMP后清洗中颗粒的去除

Removal of particles by compound surfactant in post-Cu-CMP cleaning

选用阴离子表面活性剂脂肪醇聚氧乙烯醚硫酸钠(AES,体积分数0.1%)和非离子表面活性剂异辛醇聚氧乙烯醚(JFC-E,体积分数0.25%)复配的清洗液(pH=10.3)去除铜布线化学机械抛光(CMP)后表面残留的SiO2颗粒。研究了2种表面活性剂的体积比对复配溶液的润湿性能、在铜表面的吸附情况、清洗效果和对清洗后铜表面状态的影响。结果表明,按AES和JFC-E的体积比2∶3复配的清洗液具有最佳的润湿性能和吸附效果,并且对颗粒的去除效果最好,对铜表面状态的影响最小。

The cleaning solution(pH=10.3)which was composed of an anionic surfactant i.e.sodium fatty alcohol polyoxyethylene ether sulfate(AES,0.1vol.%)and a nonionic surfactant i.e.isooctyl alcohol polyoxyethylene ether(JFC-E,0.25vol.%)was used to remove the residual SiO2 particles on the surface of copper wirings after chemical mechanical polishing(CMP).The effect of the volume ratio of the two surfactants on the wettability of the compound solution,the adsorption of surfactants on copper surface,the cleaning effectiveness,and the state of the cleaned copper surface was studied.The results showed that the compound solution with AES and JFC-E at a volume ratio of 2:3 had the best wettability,adsorptivity,and particle removal efficiency,and the least effect on the copper surface state.