Design and fabrication of superconducting transition edge X-ray calorimeters

We report on progress made so far at NASA Goddard Space Flight Center towar ds the development of arrays of X-ray microcalorimeters as candidates for t he high-resolution X-ray spectrometer on the Constellation-X mission. In th e design concept presently under consideration, the microcalorimeter consis ts of(i) a Bi/Cu multilayer absorber for stopping and thermalizing the inci dent X-rays, (ii) an e-beam evaporated Mo/Au proximity bilayer with sputter ed Nb leads for sensing the resultant temperature rise, and (iii) a silicon nitride membrane to provide a weak thermal link to the sink temperature so that the calorimeter can return to its equilibrium temperature. Fabricatio n details and preliminary results are reported. (C) 2000 Elsevier Science B .V. All rights reserved.