Publications (2)3.36 Total impact
-
Article: New cryoelectronic detector concept based on two‐dimensional heat diffusion
[show abstract] [hide abstract]
ABSTRACT: Superconducting Nb/AlO x /Nb tunnel junctions have been fabricated on Si membrane windows of only 1.2 μm thickness acting as substrates. The membrane windows with areas between (600 μm)<sup>2</sup> and (1200 μm)<sup>2</sup> remained undamaged after the different fabrications steps. The tunnel junctions positioned on the membranes and the bulk silicon substrate have very similar current‐voltage characteristics. Using low‐temperature scanning electron microscopy the two‐dimensional heat diffusion process has been imaged in the detector geometry. This two‐dimensional heat diffusion leads to a new cryoelectronic radiation detector concept combining high energy and spatial resolution with a large effective detector area. Applications of this detector concept include soft‐x‐ray spectroscopy and the nuclear β decay.Journal of Applied Physics 04/1993; · 2.17 Impact Factor -
Article: Superconducting Nb/AlOX/Nb tunnel junctions on micromachined silicon substrates
[show abstract] [hide abstract]
ABSTRACT: Combining superconducting circuit and microfabrication technology, superconductingNb/AlO X /Nb tunnel junctions (STJs) have been fabricated on Si-membrane windows of 1–2 m thickness acting as substrates. The membrane windows with areas of (10 m) 2 to (1000 m) 2 remained undamaged after the different fabrication steps. Furthermore, the STJs positioned on the membranes and on the bulk silicon substrate show similar current-voltage characteristics. The investigation of a large area STJ entirely covering a (120 m) 2 membrane window allowed to compare the detector performance in the membrane area and on bulk substrate for the same STJ under identical operation conditions. Low Temperature Scanning Electron Microscopy was applied to image the time evolution of the two-dimensional signal distribution of the device for the detection of 5 keV electrons. At T=2.1 K the number of quasiparticles generated and counted in the membrane area is increased by a factor of 10 as compared to identical energy deposition into the detector regions covering the bulk substrate. However, the strong improvement of the counting efficiency in the membrane geometry under study is combined with a spatially inhomogeneous signal distribution. Advantages and disadvantages of the membrane configuration are discussed with respect to applications in x-ray spectroscopy.Journal of Low Temperature Physics 01/1993; 93(3):617-622. · 1.19 Impact Factor
Top co-authors
Top Journals
Institutions
-
1993
-
Universität Bremen
Bremen, Bremen, Germany -
Eberhard-Karls-Universität Tübingen
- Institute of Physical and Theoretical Chemistry
Tübingen, Baden-Wuerttemberg, Germany
-
