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Superconducting Quantum Interference Filters (SQIFs) are arrays of superconducting loops of different sizes including Josephson Junctions (JJ). For a random distribution of sizes, they present a non-periodic response to an applied magnetic field, with an extended linear regime and a sizable field sensitivity. Such properties make SQIFs interesting devices to detect the magnetic component of electromagnetic waves at microwave frequencies. We have used the highly scalable technique of ion irradiation to make High Tc SQUIDs and SQIFs based on commercial YBa2Cu3O7 films, and studied their properties. Both display optimum performances as a function of temperature and bias current, that can be understood in the frame of numerical simulations that we developed. The role of asymmetries and spread in JJ characteristics (routinely found in HTSc technologies) is described : ion irradiation based devices appear robust against them. We finally present results on SQIF made with 2000 SQUID in series, showing a transfer function dV/dB ~ 1000V/T ., Comment: 16 pages, 6 figures

The large area (2D) technology for high temperature superconducting (HTS) Josephson junctions and circuits we are developing is based on the ion damage process established at LPEM [1, 2]. The aim of this work was to do a statistical analysis of the effect of geometrical parameters on Josephson junctions properties. Only junction length and barrier thickness are varied; film thickness is kept constant at a nominal 150nm. Statistical analysis of characteristic parameters (Ic, Rn, temperature range of operation...) is presented.