Evaluation of electron lifetime for Te inclusions free CdZnTe

• Published in: Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment Accelerators, spectrometers, detectors and associated equipment, 2023-10, Vol.1055, p.168487, Article 168487
• Main Authors: Kim, Kihyun, Bolotnikov, Aleksey E., James, Ralph B.
• Format: Article
• Language: English
• Subjects: CdZnTe; INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; Mobility-lifetime product; Te inclusions free; Time-of-flight; Two-step annealing
• ISSN: 0168-9002; 1872-9576
• DOI: 10.1016/j.nima.2023.168487

Te secondary phase defects are known as major obstacle for improving charge carriers transport properties of CdTe compounds material. The enhanced detector performance was reported for Te inclusions free CZT detector implemented through two-step annealing (i.e., first in Cd and second in Te). We applied the time-of-flight (TOF) technique to measure the electron lifetime in as-grown and two-step annealed CZT material. TOF has several advantages over Hecht equation fitting such as independence of the electric field distribution, direct measurement of carrier lifetime, and high accuracy for high mobility-lifetime product CZT material. The detector performance improved drastically for the two-step annealed CZT detector except which containing inordinate number and size of prismatic punching defects. The average electron lifetime increased more than 10 times after successful two-step annealing. •Electron lifetime increased more than 10 times after successful two-step annealing.•The aggregate of small-sized Te inclusions also generate prismatic punching defect.•TOF technique provide more reliable μτ products than Hecht equation for >10−2 cm2/V.