Effects of electrode fabrication on electrical properties of CdMgTe room temperature radiation detectors. (January 2023)

• Record Type: Journal Article
• Authors: Yu, Pengfei; Gao, Pandeng; Jiang, Biru; Han, Zhao; Zhao, Shiwei; Liu, Wenfei; Sun, Xing; Luan, Lijun; Rao, Tianjing
• Is Part Of: Materials science in semiconductor processing. Volume 153(2023)
• Publication Date: 2023-01
• Subjects: CdMgTe crystals -- Electrode -- Resistivity -- Energy resolution -- Carrier mobility; Semiconductors -- Periodicals; Integrated circuits -- Materials -- Periodicals; Semiconducteurs -- Périodiques; Circuits intégrés -- Matériaux -- Périodiques; Electronic journals; 621.38152
• DOI: 10.1016/j.mssp.2022.107178
• Languages: English
• ISSNs: 1369-8001

Abstract

Abstract: Cd1- x Mg x Te (CdMgTe) is an ideal alternative material for room temperature radiation detectors. In this paper, the effects of different electrode structures on the performance of CdMgTe detectors were studied. The electrodes were prepared by vacuum evaporation and chemical precipitation method using Au and Al materials. The results indicated that CdMgTe detectors with Au/CdMgTe/Al electrode structure prepared by vacuum evaporation method had the best electrical properties. For the crystals grown by Cd-excess and Te-rich conditions, the resistivity were 2.89 × 10 11 Ω cm and 3.8 × 10 11 Ω cm, the leakage current (under 100 V bias voltage) were 4 nA and 3 nA, and the Hall mobility were 2.73 × 10 3 cm 2 V −1 s −1 and 3.69 × 10 2 cm 2 V −1 s −1, respectively. The conductive type of the crystals were weak n-type. 241 Am @ 5.48 MeV α particle spectra of the detectors showed that the optimal energy resolution were 8.66% and 8.62%, and the carrier mobility-lifetime products (μτ)e were 1.47 × 10 −3 cm 2 /V and 1.03 × 10 −3 cm 2 /V, respectively. Moreover, the carrier mobility obtained by time-of-flight (TOF) test were 15.01 cm 2 /(V·s) and 77.79 cm 2 /(V·s), respectively. Graphical abstract: This figure is the energy spectra of CdMgTe detectors fabricated by three different electrodes. The energy resolution of CdMgTe detectors are compared. Image 1 Highlights: CdMgTe crystal is an ideal room temperature radiation detection material with unique advantages. The effects of electrode fabrication on the electrical properties of the detectors are investigated. CdMgTe crystal with Au/CdMgTe/Al structure prepared by vacuum evaporation method has the best electrical properties. The carrier mobility of CdMgTe crystal is studied by time-of-flight technology.