Electrical properties and X-ray spectrum of semi-insulating CdZnTe:Pb crystals

High purity Pb-doped CdZnTe single crystals were grown by using the vertical Bridgman method. Their electrical properties and X-ray spectrum were investigated. The doping concentration of Pb was about 1×1019cm-3. The resistivity of Pb-doped CdZnTe single crystal was 2×109Ωcm. The temperature dependence of the resistivity of these crystals was examined between the region of 200 and 300 K. The plot of log(ρ) versus 1000/T1000/T was represented by a straight line with a slope of 380 meV. From the PL spectrum, we have confirmed that type conversion from p to n-type conductivity originated from the compensation process of Cd vacancies, which are the most abundant acceptors in CdZnTe. Also, the effects of Pb-doping on the mobility and X-ray spectra were studied by time-of-flight (TOF) and 241Am spectrum measurements.