Novel method for fabricating deep submicron Nb/AlOx/Nbtunnel junctions based on spin-on glass planarization

摘要

A novel method for the fabrication of sub-1-μm Nb/AlOx /Nb tunnel junctions has been developed, that is based on spin-on glass planarization. The Nb/AlOx/Nb sandwich and the Nb wiring layer are structured by reactive ion etching using e-beam lithography. The insulation between the base electrode and the wiring layer is realized by planarised spin-on glass. Single electron transistors with junction areas of 0.3 μm×0.3 μm and linear arrays of junctions with sizes down to 0.5 μm×0.5 μm have been fabricated and measured