Superconducting tunnel-junction x-ray detectors with niobium absorbers and aluminum quasi-particle traps
Abstract
We are developing superconducting tunnel junction devices for use as high-resolution, high- efficiency x-ray spectrometers. We have tested devices with niobium x-ray absorbing layers coupled to aluminum layers which serve as quasiparticle traps. These devices were fabricated photolithographically using a modified niobium/aluminum/niobium trilayer fabrication process. Our first devices have a very thin barrier with specific normal state resistance of 1.5 X 10(superscript -6) (Omega) cm(superscript 2), and also exhibit very low leakage current of 15 nA below 200 mK. The energy resolution at 6 keV is 190 eV FWHM, and is limited both by electronic noise and by the non-linear response of the detector.
- Publication:
-
EUV, X-Ray, and Gamma-Ray Instrumentation for Astronomy III
- Pub Date:
- October 1992
- DOI:
- 10.1117/12.130694
- Bibcode:
- 1992SPIE.1743..328L
- Keywords:
-
- Elementary Excitations;
- Superconducting Devices;
- Trapped Particles;
- Tunnel Diodes;
- X Ray Detectors;
- X Ray Spectroscopy;
- Aluminum;
- Cryogenic Cooling;
- Demagnetization;
- Niobium;
- Volt-Ampere Characteristics;
- Instrumentation and Photography