Title:
ETCHING SOLUTION
Document Type and Number:
Japanese Patent JP2005256077
Kind Code:
A
Abstract:
To provide an etching solution which does not damage polycrystal Si(poly-Si) and a Si oxide film (SiO2), has a highly selective etching rate to a hafnium oxide film of a hardly-soluble high-dielectric material used as a gate insulation film, and does not include hydrofluoric acid.
The etching solution includes phosphorous acid and/or phosphoric acid which has silicon dioxide dissolved therein. The silicon dioxide dissolved in the phosphorous acid and/or phosphoric acid is preferably saturated or supersaturated.
Inventors:
TAKAHASHI FUMIHARU
HARA YASUSHI
HAYASHI HIROAKI
HARA YASUSHI
HAYASHI HIROAKI
Application Number:
JP2004068784A
Publication Date:
September 22, 2005
Filing Date:
March 11, 2004
Export Citation:
Assignee:
TOSOH CORP
International Classes:
C23F1/20; C23F1/30; H01L21/308; H01L29/78; (IPC1-7): C23F1/20; C23F1/30; H01L21/308; H01L29/78