use piranha cleaning if your sample don't have metal layer, or O2 RIE cleaning. On Mon, 07 Nov 2011 22:49:48 +0800, Judith Linacero Blancowrote: > Hello everyone, > > I made a lithography by e-beam with lines of 200nm separated 200nm with > 300nm of PMMA on silicon. > > Once I etch the silicon with RIE, and then I try to clean the > sampleacetone, > sonicated. The problem is that I still have traces of PMMA in the sample, > and I can't clean at all the sample. > > Can anyone help? How I can clean the whole sample of e-beam lithography? -- Sincerely Jack, Zetao MA Dept.of EEE, CYC712,HKU