Published online by Cambridge University Press: 28 February 2011
Etch inhibitor layers are the key to anisotropy for a number of dry etch processes, yet little is known about these layers because of the difficulty in analyzing them on the side walls where they form. In this paper we will show that an Al grid suspended above an etching surface can be used to suppress ion bombardment and allow the inhibitor to form on large horizontal surfaces which can be easily analyzed. The effect of ion bombardment on the nature of the inhibitor layer can also be elucidated using this technique. In conjunction with X-ray Photoelectron Spectroscopy, this method was used to look at the polymeric inhibitor formed during Si etching in SF6/C2CIF5 with and without the presence of photoresist.