Abstract: Disclosed herein is a composition for removing post-etch residues in the presence of a layer comprising silicon and a dielectric layer including a silicon oxide, the composition including: (a) 0.005 to 0.3 % by weight HF; (b) 0.01 to 1 % by weight of an ammonium fluoride of formula NRE4F, where RE is H or a C1 to C4 alkyl group; (c) 5 to 30 % by weight of an organic solvent selected from the group consisting of a sulfoxide and a sulfone; (d) 70 % by weight or more water, and (e) optionally 0.01 to 1 % by weight of an ammonium compound selected from the group consisting of ammonia and a C4 to C20 quaternized aliphatic ammonium.