We measured the total body capacitance of an irradiated (ATT7) and an unirradiated detector
(UCSC2) to determine the total depletion voltage of the detectors. The method to measure
the body capacitance is descriped here. Since these two
detectors were already mounted to a hybrid, we measured the total capacitance between
bias ring and backplane with the full bias voltage supplied to the backplane.
To limit the leakage current of the irradiated detector (ATT7), we cooled it down to -20C
with liquid nitrogen.