FA/O精抛液组分对Cu/Ta CMP去除速率的影响

Effect of FA/O Fine Polishing Slurry Components on the Removal Rate of Cu/Ta CMP

研究了精抛液中各组分对Cu/Ta去除速率的影响。在分别考察磨料质量分数、Ⅱ型螯合剂、活性剂和双氧水等各组分对Cu/Ta去除速率的影响后,研发了磨料质量分数为2%,Ⅱ型螯合剂体积分数为0.35%,活性剂体积分数为2%,H2O2体积分数为2%的FA/O精抛液。并在MIT854布线片上进行了精抛测试。结果显示,精抛12 s之后,100-100线条处高低差从精抛前的76.7 nm降低为63.2 nm,而50-50线条处高低差从精抛前的61.3 nm降低为59.8 nm。并且,经过FA/O精抛液精抛后粗抛后产生的尖峰也有所减小,台阶趋于平坦。精抛后,100-100和50-50处的高低差均小于70 nm,能够达到产业化指标。

The components of fine polishing slurry, including abrasive concentration, chelating agentⅡ,active agent and H2O2 effect on removal rate of Cu / Ta were investigated respectively. Based on these researches,an FA / O fine polishing slurry was developed with a mass fraction of 2% abrasive,the volume fraction of 0. 35% chelating agentⅡ,the volume fraction of 2% active agent and the volume fraction of 2% H2O2. Then the FA / O fine polishing slurry was tested on the MIT854. The results show that the step-height of 100- 100 line width was reduced from 76. 7nm to 63. 2nm,and 50- 50 line width reduced from 61. 3nm to 59. 8nm after 12 s finishing polish. The spikes caused by rough polishing were also decreased and the steps were more planar. Through FA / O fine polishing,the height-difference of line width with 100- 100 and 50- 50 were all less than 70 nm,which meet the demand of industry requirement.