Characterization of the Superconducting Transition of Thin Ir Films for TES

We are currently producing iridium based TESs for a wide variety of applications such as single photon detection of the visible and infrared light, X-ray spectroscopy and low energy nuclear beta and electron capture spectroscopy for neutrino mass search experiment. We present a study of the TES performance related to the superconductivity properties of the Ir film as function of the production processes, that depend on substrate type: Si or SiN, and of the operating electrical parameters. Moreover we developed a finite element model of thin superconducting film, by which we obtain qualitative agreement between experimental and simulated data.