We present experimental results from the microfabrication and characterization of nanostructured thin films within prototype devices, which we refer to as Meissner-effect transition-edge-sensors, that may ultimately be utilized for sensing applications including microscale magnetometry and microcalorimetry. For the devices reported here, the change in magnetic flux from a microscale disk of electrodeposited tin may be detected by a planar pickup coil consisting of a niobium nanostructured thin film. The optimization of the nanostructured thin films requires sufficient control of sputtering deposition parameters including chamber pressure, gas flow, and power. Multiple mechanisms provide nanostructured pathways for infiltration of the niobium thin film during deposition. The nanostructured thin films were experimentally characterized in terms of thickness, stress, room-temperature resistivity, and resistance as a function of temperature. We find that the superconducting transition temperature for the niobium nanostructured thin film pickup coils spans a significant range from approximately 4 Kelvin to 11 Kelvin depending on the sputtering deposition parameters. We target operation in the regime where the microscale tin disk is in the transition between the normal and superconducting states but the nanostructured thin film pickup coil is fully superconducting and therefore compatible with Superconducting Quantum Interference Device (SQUID) readout.
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