Fabrication of Sub-Micrometer SIS Junctions for Radio Astronomy

Author

Krebs, N. ; Barbier, A. ; Billon-Pierron, D. ; Halleguen, S. ; Schicke, M. ; Schuster, K.F.

Author_Institution

Inst. de Radio Astron. Millimetrique (IRAM), St. Martin d´´Heres

Volume

17

Issue

2

fYear

2007

fDate

6/1/2007 12:00:00 AM

Firstpage

191

Lastpage

193

Abstract

We present a new fabrication scheme for high quality Nb-AlO_x-Nb junctions as used for mm-wave mixers in radio astronomy. The key features of the fabrication process are high-resolution e-beam lithography for junction and contact definition as well as highly selective Niobium and SiO₂ inductively coupled plasma etching. Chemical-mechanical polishing, which is difficult to control for low volume production is not required. We further show that a new type of spin-on glass can be used as a reliable replacement for sputtered SiO₂. We present yield and parameter scattering of these devices.

Keywords

aluminium compounds; electron beam lithography; millimetre wave mixers; niobium; polishing; radioastronomy; sputter etching; superconductor-insulator-superconductor mixers; Nb-AlO-Nb; Nb-AlO_x-Nb junctions; SiO₂; chemical-mechanical polishing; coupled plasma etching; electron-beam lithography; fabrication scheme; low volume production; parameter scattering; radio astronomy; spin-on glass; submicrometer SIS junctions; superconductor-insulator-superconductor junctions; Chemical products; Fabrication; Lithography; Niobium; Plasma applications; Plasma chemistry; Plasma devices; Production; Radio astronomy; Sputter etching; Millimeter wave mixers; radio astronomy; superconducting device fabrication; thin films;

fLanguage

English

Journal_Title

Applied Superconductivity, IEEE Transactions on

Publisher

ieee

ISSN

1051-8223

Type

jour

DOI

10.1109/TASC.2007.898717

Filename

4277532