Sn electrodeposition process for fabricating microabsorber arrays for an X-ray microcalorimeter

Sn electrodeposition was employed for fabricating an array of microabsorbers with a ‘mushroom-shaped’ microstructure for a precision X-ray microdetector, the so called X-ray microcalorimeter. A deposition process for flat and smooth Sn films, which was suitable for the use of the absorber material, was developed by optimizing the conditions of additives such as o-cresol-4-sulfonic acid and polyethyleneglycol (PEG) to the Sn bath. The Sn films exhibited suitable properties, i.e. a higher superconducting transition temperature than the operating temperature of the X-ray microcalorimeter. The mushroom-shaped absorber array was successfully fabricated by Sn electrodeposition in combination with a photolithographic technique.