半导体学报2009，Vol.30Issue(12)：133-136,4.DOI:10.1088/1674-4926/30/12/126001
TaN wet etch for application in dual-metal-gate integration technology
TaN wet etch for application in dual-metal-gate integration technology
摘要
Abstract
Wet-etch etchants and the TaN film method for dual-metal-gate integration are investigated. Both HF/HN O_3/H_2O and NH_4OH/H_2O_2 solutions can etch TaN effectively, but poor selectivity to the gate dielectric for the HF/HNO_3/H_2O solution due to HF being included in HF/HNO_3/H_2O, and the fact that TaN is difficult to etch in the NH_4OH/H_2O_2 solution at the first stage due to the thin TaO_xN_y layer on the TaN surface, mean that they are difficult to individually apply to dual-metal-gate integration. A two-step wet etching strategy using the HF/HNO_3/H_2O solution first and the NH_4OH/H_2O_2 solution later can fully remove thin TaN film with a photo-resist mask and has high selectivity to the HfSiON dielectric film underneath. High-k dielectric film surfaces are smooth after wet etching of the TaN metal gate and MOSCAPs show well-behaved C-V and J_g-V_g characteristics, which all prove that the wet etching of TaN has little impact on electrical performance and can be applied to dual-metal-gate integration technology for removing the first TaN metal gate in the PMOS region.关键词
TaN/ wet etching/ metal gate/ high k dielectric/ integrationKey words
TaN/ wet etching/ metal gate/ high k dielectric/ integration分类
信息技术与安全科学引用本文复制引用
Li Yongliang,Xu Qiuxia..TaN wet etch for application in dual-metal-gate integration technology[J].半导体学报,2009,30(12):133-136,4.基金项目
Project supported by the Special Funds for Major State Basic Research Projects (No. 2006CB302704) and the National Natural Science Foundation of China (No. 60776030). （No. 2006CB302704）
