Fabrication of Metallic Magnetic Calorimeter for Radionuclide Analysis

We present a detailed report on the fabrication process of a metallic magnetic calorimeter (MMC). The MMC is configured in a planar geometry with a meander-shaped pickup coil covered with a Au:Er temperature sensor layer. The meander coil is used to apply a magnetic field to magnetize the erbium ions and to measure the magnetization change of the spin system. The MMC is designed to have a large area (1 mm\(^2\)) and 3 \(\upmu \)m thickness Au:Er layer, which is suited for large metal absorbers with a few nJ/K heat capacity in radionuclide analysis applications. The completed devices are used in alpha and Q spectrometries.