Offset masks for lift-off photoprocessing

We describe a technique using photolithography to produce submicron-scale thin-film structures and simple multilevel structures by single-mask lift-off processing. The technique employs masks offset from the substrate and oblique angle thin-film deposition. It provides a simple means of making small-area Josephson junctions and varying-thickness superconducting bridges and is suitable for the inclusion of these devices in circuits. The examples we show emphasize such applications in superconductivity; however, the technique may find uses in other fields as well.