钛基片的化学机械抛光技术研究

采用化学机械抛光（CMP）方法对钛基片进行纳米级平坦化处理，通过系列抛光试验优化抛光液组成和抛光工艺条件后，得到AFM-Ra为0.159 nm的纳米级抛光表面和156.5 nm/min的抛光速率。抛光液的电化学分析结果表明：二氧化硅颗粒和乳酸在钛表面有不同程度的吸附缓蚀作用，氨水和F-的络合、扩散作用能破坏缓蚀膜层，两者的中间平衡状态才能得到最佳抛光效果。抛光后钛表层XPS测试结果显示钛表层经过化学氧化形成疏松氧化层后，再通过磨粒和抛光垫的机械作用去除。

Nanoscale Planarization Mechanism of Titanium Chemical Mechanical Polishing

Chemical mechanical polishing (CMP) with colloidal silica which is widely used in ULSI was proved to be sufficient to produce the nanoscale roughness on titanium surface. Experiments were done to optimize the polishing process parameters and examine the effect of some slurry parameters, and an optimum Ti CMP slurry with appropriate material removal rate (MRR) as 156.5 nm/min and low average roughness (Ra) as 0.159 nm by AFM was gotten. The results of electrochemical analysis showed that the synergism of adsorption of SiO2 and lactic acid on Ti surface and destructive effect of ammonia and F- to adsorption film was critical to get optimum polishing results. And XPS results supported the planarization mechanism that loose TiO2 oxide layer was formed during polishing process which could be removed efficiently by mechanical grinding of abrasive particles and polishing pad.