Co-integration of Airbridges and 3D Integration Modules

A method for fabricating one or more airbridge structures and one or more 3D integration modules on a patterned metallization layer of a wafer comprising qubits or superconducting electronics, the method comprising:

• providing the wafer with the patterned metallization layer;
• depositing an integrated metallization layer on the wafer, before or after providing and patterning a first resist layer;
• forming one or more airbridge structures, wherein:
• the one or more airbridge structures contact the patterned metallization layer at openings in the first resist layer;
• the one or more airbridge structures are superconductive at operating temperatures;
• the integrated metallization layer is between the one or more airbridge structures;
• and
• the patterned metallization layer is superconductive at operating temperatures, at least due to a proximity effect, or provides a galvanic contact between the one or more airbridge structures and the patterned metallization layer with a resistance smaller than a predefined threshold at operating temperatures, for preserving qubit coherence or maintaining superconductivity in superconductive electronics;
• and
• fabricating one or more 3D integration modules by electroplating predefined regions of the integrated metallization layer.