A novel two-step Al CMP process for overcoming pattern geometry effects

被引：1

作者：

Tsai, MS ^{[1
]}

Lin, JS ^{[1
]}

Dai, BT ^{[1
]}

机构：

[1] Natl Nano Device Labs, Hsinchu 30050, Taiwan

来源：

MULTILEVEL INTERCONNECT TECHNOLOGY II | 1998年 / 3508卷

关键词：

aluminum alloys; chemical-mechanical polishing; pattern geometry effects; slurry formulation;

D O I：

10.1117/12.324029

中图分类号：

TP3 [计算技术、计算机技术];

学科分类号：

0812 ;

摘要：

It is important and critical to obtain reasonable removal rate, low polish non-uniformity, scratchless polished surface and no metal dishing and ILD erosion for aluminum damascene process with CMP It is difficult to meet these requirements in a single-step polishing process because lower removal rate of titanium, known as polish-inert metal, results in significant over-polish of the aluminum features and severe metal dishing and ILD erosion should be obtained. Here we evaluate a novel 2-step polishing process to accomplish the damascene process more efficiently. First, the overburden aluminum tvas removed fast and uniformly. In our study more than 3,000 nm/min removal rate, less than 10% polish non-uniformity and scratchless finished surface could be obtained. Next, by adjusting slurry pH, the removal rare of Al could be about as the same as that of Ti and that of SiO2 unchanged in the meantime. By this way, it relaxes the process window to overcome the problems of the pattern geometry effects.

引用

页码：216 / 223

页数：8