Title :
Fabrication of SIS junctions for space borne submillimeter wave mixers using negative resist e-beam lithography
Author :
Péron, Isabelle ; Pasturel, Patrice ; Schuster, Karl-Friedrich
Author_Institution :
DEMIRM, Obs. de Paris, Meudon, France
fDate :
3/1/2001 12:00:00 AM
Abstract :
We report on the development of a new process for the fabrication of Nb/Al-AlOx/Nb tunnel junctions for channel 1 (480-640 GHz) Superconductor-Insulator-Superconductor (SIS) mixers of HIFI, the Heterodyne Instrument for FIRST (Far InfraRed & Submillimeter Telescope). The process is derived from a standard self-aligned lift-off process but uses negative resist electron beam lithography (EBL) for junction definition. The junction area is tightly controlled down to below 1 μm2 without the complexity of processes using positive electron beam resists. We describe process parameters and experimental results: DC-tests and Fourier Transform Spectrometer (FTS) measurements
Keywords :
aerospace instrumentation; aluminium; aluminium compounds; electron beam lithography; electron resists; niobium; submillimetre astronomy; submillimetre wave mixers; superconductor-insulator-superconductor mixers; 480 to 640 GHz; DC testing; FIRST; Fourier transform spectrometry; HIFI; Nb-Al-AlO-Nb; Nb/Al-AlOx/Nb SIS tunnel junction; heterodyne instrument; negative resist electron beam lithography; self-aligned lift-off process; space borne submillimeter wave mixer; submillimeter telescope; Electron beams; Fabrication; Instruments; Josephson junctions; Niobium; Resists; Submillimeter wave devices; Superconducting devices; Superconducting photodetectors; Telescopes;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
