RESOLUTION DEGRADATION OF COAXIAL P-TYPE GERMANIUM DETECTORS DUE TO HOLE TRAPPING BY POINT-DEFECTS

A quantitative relationship has been experimentally determined correla tion the resolution degradation of p-type coaxial high-purity germaniu m detectors to the concentration of residual hole-trapping point defec ts. Detector diameters ranged from 48 to 65 mm, and the average electr ic-field strength was 1500 V/cm. The concept of a ''standard level'' i s proposed, which originates in the similar capture kinetics of many c ommonly observed residual acceptors in high-purity germanium. A method for calculating the electric-field dependence of hole capture is pres ented and used to compare the data reported here with published modeli ng results parameterized by the mean-free-drift length. Good general a greement is found.