Abstract: A shadow mask for sputtering is formed from a single crystal silicon wafer which is mechanically and chemically polished to produce top and bottom surfaces which are substantially flat and parallel to one another. The wafer is provided with one or more pyramidal etch pits which are arranged in a pattern. Each pit has a substantially square cross-section on the top surface, and a smaller substantially square cross-section on the bottom surface to produce an aperture in the wafer. In use, the wafer is clamped against a flat substrate with its apertures opening toward the evaporant beam. After use, the deposited species may be cleaned from the wafer using suitable etchants which render the wafer unharmed, and therefore reusable.