Membrane mask for electron beam lithography

摘要

Membrane masks for electron-beam lithography are described which have a high mechanical stability and low membrane thickness, are free of stress and the submicron structures of which are easy to produce using reactive ion etching methods without rounding effects. In the case of a membrane mask for structuring surface areas with the aid of electron or corpuscular beams, a layer 1 of silicon nitride with going right through openings, which define the mask pattern, is deposited on one surface of a semiconductor wafer 2, which consists preferably of silicon. A tub-shaped recess 3 extends from the other surface of the semiconductor wafer 2 as far as the layer-carrying surface. A further mask for structuring surface areas with the aid of electron beams has at least one continuous layer 30 and a layer 31 defining the mask pattern. These two layers are deposited on the surface of a semiconductor wafer 32 with a tub-shaped recess 33. The anisotropic plasma etching method according to the invention makes it possible to transfer lithographically produced patterns to the membrane without the edge rounding which is otherwise usual.