冗余金属对互连线电容特性的影响

Influence of dummy fill on interconnect capacitance

在深亚微米尺寸的集成电路设计中,可制造性设计变得越来越重要。从180 nm时代开始,铜互连代替铝已成为趋势,但是铜在制造工程中难刻蚀,因此在工业上引入了化学机械研磨。为了使化学机械研磨取得好的平坦化效果,必须预先改善设计,对版图金属布局进行冗余金属填充,使之满足工艺生产要求。因此,对版图金属布局进行冗余金属填充,成为研究的热点。文章研究了冗余金属的各种因素对互连线电容特性的影响,并在此基础上给出了优化的冗余金属填充方案。

For advanced interconnect technologies with sub-micron dimensions,design for manufacturability（DFM） has become more and more important.Since the beginning of 180 nm era,copper metallization has replaced traditional aluminum technology in the interconnect technology,but it is hard to be eroded,so the chemical-mechanical polishing（CMP） is brought in.In order to achieve chemical-mechanical planarization,it is necessary to amend the design beforehead and insert dummy fill into low-density layout regions to meet the requirement of manufacture,which has become a popular research issue nowadays.In this paper,the influence of dummy fill on interconnect capacitance is analyzed with the variations of possible factors,and based on it,the optimized design for dummy fill is proposed.