A silicon shadow mask for deposition on isolated areas

A shadow mask with high pattern flexibility is realized by deep reactive ion etching (RIE) on Si wafer. The novel features of the mask are the presence of a mechanical alignment structure and of patterns with isolated islands inside them. The advantage of this shadow mask is the possibility of deposition of any kind of pattern shape by evaporation or sputtering on a sample that is precisely positioned. Moreover, by this technique, deposition is realized without damaging electronic devices or micromachined structures on the sample. Precise positioning of the sample with respect to the shadow mask is allowed by the mechanical alignment structures. Some doughnut-shape-like patterns are obtained by deposition through the patterns with isolated islands inside them. In this article we will describe the realization and the application of such a shadow mask.