High Detection Performance of Particle Detectors Based on SI InP Doped With Ti and Zn

In this work, we present results of measurements of spectra of alpha-particles carried out on semi-insulating (SI) InP detectors. The detectors were fabricated from Ti and Zn co-doped SI InP crystals grown by Czochralski technique. Tests of detectors performance with alpha-particles emitted from ²⁴¹Am (5.48 MeV) radioactive source are reported. Excellent detectors performance has been evaluated by values of charge collection efficiency 99% and energy resolution ~ 1% obtained from the spectra measured at 230 K. Such high performance can be explained by InP doping with suitable Ti atoms and co-doping with low concentration of Zn acceptors sufficient for the full compensation of shallow donors, to reach SI properties. The electron mobility of reported SI InP detectors co-doped with Ti and Zn has been found to be equal to 2510 cm² V^-1 s^-1 at room temperature. This value is much higher than that obtained previously with our SI InP co-doped with Ti and Mn or with InP crystals converted to SI state by temperature annealing. Excellent detector performance and high electron mobility makes the reported InP material promising to be used for the detection of X-rays and gamma-radiation.