Study of Charge Transport in a SuperCDMS-style Ge Detector Fabricated From a USD-Grown Single Crystal at a Cryogenic Temperature

A designated experiment to understand the charge transport behavior in a SuperCDMS-style Ge detector made from a USD-grown crystal was performed at the University of Minnesota. The detector is patterned with four concentric charge channels on one side, and a bias electrode on the opposite side. Am-241 sources were used to observe the 59.54 keV peak in spectra from each channel. Since the majority of charge carriers were created near the surface of the detector, this study can be used to understand the charge transport, charge collection efficiency, charge trapping, and charge breakdown, as a function of bias voltage. We investigated the time-dependent charge amplification induced by holes at mK temperature.