This report describes the preparation of superhydrophobic and oleophobic sur faces by grafting of poly(perfluorodecylacrylate) chains with initiated chemical vapor deposition on silicon substrates. The grafting enhances the formation of a semicrystalline phase. The crystalline structures reduce the polymer chain mobility, resulting in nonwetting surfaces with both water and mineral oil. On the contrary, the same contacting liquid easily wets the amorphous ungrafted polymer.