New methods for evaluation of mobility-lifetime product (mu-tau) in polarized planar CdTe and CdZnTe detectors are presented. We combined the transient-current technique measurements with the measurements of the charge-collection efficiency and developed two iterative procedures for calculating mu-tau and mobility both taking into account the actual profile of the electric field in a detector.
Their applicability is demonstrated on both the simulated and existing experimental data. The cases in which these methods are preferred to the common procedures based on the Hecht equation are widely discussed.
We demonstrate that neglecting the detector's polarization can lead to underestimation of real mu-tau, thus negatively affecting the interpretation of particular measurements.