COUPLED 2D-ARRAYS OF JOSEPHSON-JUNCTIONS

As a first step toward fabricating a truly-3D Josephson junction array we have developed a fabrication technology to stack 2D-arrays of Jose phson junctions on top of ead other. The coupling between the array is capacitive and/or inductive. We describe in detail the fabrication te chnique which consists of a four-layers process including electron bea m lithography with alignment. Fabrication efforts are especially devot ed to arrays with large junctions (0.5 mu m(2)) for studying interacti on of vortices through inductive coupling. A similar fabrication techn ology may allow us to study the interaction of vortices in one array w ith charges in the other array. The conditions for efficient coupling are discussed in both cases.