Patent ID: 7311857
Filing Date: 2007-12-25
Classification: C09K,C11D,H01L

Abstract:
1. An etching composition comprising about 0.1 to 8% by weight of hydrogen fluoride (HF), about 10 to 25% by weight of ammonium fluoride (NH 4 F), about 0.0001 to 3% by weight of a non-ionic polymer surfactant, and water (H 2 O), wherein the non-ionic polymer surfactant has a structure of H—(OCH 2 CH 2 ) x —(OCH(CH 3 )CH 2 ) y —(OCH 2 CH 2 ) z —OH, wherein x, y and z are positive integers, and wherein the average molecular weight of the non-ionic polymer surfactant is about 3,000 or less.