We propose a patterning method to form nanostructures of a Co/Pd multilayer by using electron-beam lithography with an amorphous silicon (a-Si) layer and two-step etching process. On the Co/Pd multilayer, a-Si is sputter deposited and hydrogen silsesquioxane (HSQ),. the electron-beam resist, is spin coated sequentially. We found that an a-Si intermediate layer between the Co/Pd underlayer and HSQ overlayer improves adhesion of HSQ on the metallic underlayer after electron-beam dosing and chemical development; it also increases etch selectivity between the Co/Pd multilayer and its overlayers. We demonstrate that a Co/Pd multilayer can be patterned successfully as a nanowire array using the suggested process. (c) 2006 American Vacuum Society.