Novel planarization technology of metal gate etch-back in advanced CMOS fabrication

作者：Meng Lingkuan^*; Yin Huaxiang; Xu Qiuxia; Chen Dapeng; Ye Tianchun

来源：Chinese Journal of Vacuum Science and Technology, 2012, 32(9): 793-797.

DOI：10.3969/j.issn.1672-7126.2012.09.06

• Advanced CMOS
• CMOS devices
• Dummy poly
• Feature sizes
• Gate-last
• In-situ
• Metal gate
• Nano scale
• Non-uniform distribution
• Nonuniformity
• Novel techniques
• Oxygen plasma treatments
• Planarization
• Planarization technology
• Scanning electron micrographs
• Spin on glass
• Wafer edge

A novel technique was developed to effectively planarize the high-K metal gate etch-back in the advanced CMOS fabrication, where the feature size is scaled down to 45 nm. In the newly-developed technique, the two-step spin-on-glass plasma etch-back was combined with in-situ oxygen plasma treatment. The negative effect of the non-uniform distribution of the polymer on the reactive ion-etching rate was eliminated. As a result, the thickness non-uniformity within-the-wafer (excluding the 5 mm wafer edges) can be easily realized. In the scanning electron micrographs of the planarized metal gate etch-back, no chemical-mechanical-polish-like "dish effect" was observed on both the isolated and the dense sub-micro gate-stack structures, indicating that the planarization technology does a good job for the nano-scale high-K /metal gate-last CMOS device integration.

• 出版日期2012