Charge Collection in Surface Channels on High-Purity Ge Detectors

Studies with collimated low energy ¿-ray beams show that for ¿-ray interactions within a "dead layer" of thickness about 1 mm at the surface of a Ge detector, the pulse height distribution is characteristic of single carrier collection. Independent measurements of the charge transport parameters also show that the majority carriers in the surface channel do not contribute to the charge pulse.