Patent ID: 6660655
Filing Date: 2003-12-09
Classification: C23F,H01L

Abstract:
A method for preparing SEM samples comprising low-K dielectric materials, comprising the steps of:a. providing a SEM sample comprising low-K dielectric material and silicon oxide material; and b. etching said SEM sample in a solution comprising NH4F (s) dissolved in a solution comprising HNO3 having a concentration of between about 50% and 96% and CH3COOH having a concentration of between about 90% and 100% at a volume ratio of between about 10 ml HNO3:30 ml CH3COOH and 20 ml HNO3:10 ml CH3COOH; said NH4F (s) being added at a ratio of between about 0.5 g NH4F (s):35 ml CH3COOH and HNO3 and 2 g NH4F (s):35 ml CH3COOH and HNO3.