Patent ID: 8334205
Filing Date: 2012-12-18
Classification: H01L

Abstract:
1. A method for removing polymer after etching a gate stack structure of high-K gate dielectric/metal gate, comprising: step 1): forming a gate stack structure of interface SiO 2 /high-K gate dielectric/metal gate/poly-silicon/hard mask in sequence on a silicon substrate with device isolations formed thereon; step 2): forming a resist pattern by the lithography; step 3): etching the gate stack structure; and step 4): immersing the resultant structure of step 3) in an etching solution of HF/HCl/water to remove the polymer, wherein in the etching solution the ratio of HF by volume is 0.2˜1% and the ratio of HCl by volume is 5˜15%.