Growth and fabrication method of CdTe and its performance as a radiation detector

Abstract

A CdTe crystal ingot doped with 2000 ppm of Cl was grown by using the low-pressure Bridgman (LPB) method at the Korea Atomic Energy Research Institute (KAERI). A Semiconductor detector as a radiation detection sensor with a size of 7 (W) × 6.5 (D) × 2 (H) mm³ was fabricated from the CdTe ingot. In addition, the properties of the CdTe sample were observed through four kinds of experiments to analyze its performance. The resistivity was obtained as 1.41 × 10¹⁰ Ωcm by using a Keithley 6517A high-precision electrometer. The mobility-lifetime products for electrons and holes were 3.137 × 10^-4 cm²/V and 4.868 × 10^-5 cm²/V, respectively. Finally, we achieved a 16.8% energy resolution at 59.5 keV for the ²⁴¹Am gamma-ray source. The CdTe semiconductor detector grown at KAERI has a performance good enough to detect low-energy gamma-rays.