Characterisation of the Charge Collection Properties in a Segmented Planar HPGe Detector

Segmented germanium semiconductor detectors provide excellent γ-ray spectroscopic information whilst also being sensitive to the position of interactions within their active volume. Understanding the detector response to γ-ray interactions throughout its volume is required for interpreting the signal output. This work is the first assessment of the response and charge collection properties of an electrically-cooled Mirion Technologies-manufactured planar HPGe detector with boron implanted p+ and amorphous germanium based n+ strip contacts. The signal response of the detector as a function of γ-ray interaction position has been characterised by performing collimated beam scans with 59.5 keV and 661.7 keV γ-rays. A database of average signals, generated through the detector volume and across the detector surfaces, has been produced. A map of parameterised rise time response through depth has been generated and used to apply pulse shape analysis techniques, improving the position resolution within the detector.