Patent ID: 7566666

Claim:
A method of recycling a substrate comprising: forming an insulation layer on the substrate, wherein the insulation layer comprises a low-k material and a protection material; and, removing the insulation layer from the substrate by applying to the substrate a composition comprising: about 1 to 50 percent by weight of at least one peroxy acid compound selected from the group consisting of ammonium persulfate, sodium persulfate, potassium persulfate, peroxynitric acid, peroxyphosphoric acid, peroxysulfuric acid, peroxyboric acid, sodium peroxyborate, peroxyformic acid, peroxyacetic acid, peroxybenzoic acid, and peroxyphthalic acid; about 0.1 to 35 percent by weight of a fluorine-containing compound; and water, wherein the protection material comprises at least one of silicon carbonitride (SiCN) and silicon nitride (SiN).