Resistivity variation of semi-insulating Cd1-xZnxTe in relationship to alloy composition

We investigated the resistivity variation of semi-insulating Cd1-xZnxTe use d as room temperature nuclear radiation detectors, in relationship to the a lloy composition. The resistivity and the zinc composition were determined using leakage current measurements and triple axis x-ray diffraction lattic e parameter measurements, respectively. While the zinc content of the nomin ally x(Zn) similar to 0.1 ingot varied monotonically according to the norma l freezing behavior with an effective segregation coefficient of k(eff) = 1 .15, the resistivity was found to vary non-systematically throughout the in got. Furthermore, the "expected" relationship of higher zinc content with h igher resistivity was not always observed. For example, wafer regions of x( Zn) similar to 0.12 and x(Zn) similar to 0.08 exhibited resistivity values of similar to 10(10) and similar to 10(11) Ohm.cm, respectively. In general , the experimental resistivity values can be explained by calculated values which take into account a compensating deep level defect and various elect ron and hole mobility values. The relative influence of the parameters that govern the resistivity (n, p, mu(e), and mu(h)) are quantitatively investi gated.