X-Ray Detectors Based on Amorphous InGaZnO Thin Films
Journal
IEEE Transactions on Electron Devices
Journal Volume
70
Journal Issue
7
Date Issued
2023-01-01
Author(s)
Abstract
Indium–gallium–zinc oxide (IGZO) photodetectors have been mostly studied in the ultraviolet region and rarely in the X-ray region. This study fabricates IGZO X-ray detectors on glass substrates using different post-deposition annealing (PDA) times. The photo-to-dark current ratio increases significantly from 2.6 to 392.3 after PDA because of a considerable reduction of the deep-level states. There are fewer residual electrons in the conduction band and recombination centers in the middle of the bandgap are eliminated. An IGZO X-ray detector with optimal PDA time has a sensitivity of 8.5 $\times$ 10 $^{-\text{3}}$ $\mu $ C/(mGy $\cdot$ cm $^{\text{2}}\text{)}$ and a rise/decay time of 5.1/12.2 s with a bias of 10 V at a dose rate of 100 mGy/s. This result shows that IGZO is eminently suited to applications for X-ray detection.
Subjects
Dark current | Detectors | Indium–gallium–zinc oxide (IGZO) | Performance evaluation | Photoconductivity | Photonic band gap | post-annealing | Sensitivity | X-ray detectors | X-ray detectors
Type
journal article