Space Charge Influences on Fields and Charge Collections in High Purity Germanium Detectors

Space charge influences on fields and charge collection properties in the high purity germanium coaxial and planar detectors are studied on the basis of the experimental results obtained by previous studies. Several different impurity charge densities (NA - ND = = 109 ~1011 cm-3) have been considered with a non-constant high field mobility which has been obtained by averaging the values obtained by several different investigators. A comparison with the lithium-drifted devices is given and a discussion relevant to the timing is presented.