Hi Marc, We did do deposition of Oxide in trenches of the aspect ratio of 150-200. We maintained temperatures of 800C and a mixture of dichlorosilane and nitrous oxide gases was used. The deposion rate is low but our application needed only thin oxides so we used LPCVD to deposit oxide and the deposition was conformal. Regards, Murty Ravula. __________________________________ Do you Yahoo!? Yahoo! SiteBuilder - Free, easy-to-use web site design software http://sitebuilder.yahoo.com