Low-noise X-ray PIN photodiodes made of perovskite single crystals by solution-processed dopant incorporated epitaxial growth. (November 2021)

• Record Type: Journal Article
• Authors: Wang, Xin; Xu, Yubing; Pan, Yuzhu; Li, Yuwei; Xu, Ji; Chen, Jing; Wu, Jun; Li, Qing; Zhang, Xiaobing; Zhao, Zhiwei; Li, Chi; Elemike, Elias E.; Onwudiwe, Damian C.; Akram, Javed; Lei, Wei
• Is Part Of: Nano energy. Volume 89(2021)Part A
• Publication Date: 2021-11
• Subjects: Low noise -- X-ray PIN photodiode -- Epitaxial growth -- Dopant incorporation; Nanoscience -- Periodicals; Nanotechnology -- Periodicals; Nanostructured materials -- Periodicals; Power resources -- Technological innovations -- Periodicals; Nanoscience; Nanostructured materials; Nanotechnology; Power resources -- Technological innovations; Periodicals; 621.042
• DOI: 10.1016/j.nanoen.2021.106311
• Languages: English
• ISSNs: 2211-2855

Abstract

Abstract: X-ray photodiodes made of metal halide perovskites (MHPs) which directly convert X-ray photons into electron-hole pairs have shown advantages in low-cost and high X-ray detection sensitivity. However, lattice-mismatched blocking layers deposited by spin-coating or evaporation cannot fully limit the dark current and noise current under large reverse bias. In this work, Solution-processed dopant incorporated epitaxial growth is employed to form sufficient blocking barriers through epitaxially growing lattice-matched n-type MHPs (bismuth-doped) and p-type MHPs (silver-doped) on opposite faces of intrinsic CH3 NH3 PbBr2.5 Cl0.5 MHP single crystals. Through energy structure design, electron/hole blocking layers can form sufficient charges barriers, the X-ray PDs exhibit a low leakage dark current density of ~ 11 nA cm −2 under large reverse electrical field (over 500 V cm −1 ) and noise current of 47 fAHz −0.5 (1 mm 2, over 500 V cm −1 ). The large external electrical field enables a state-of-art response speed (fall) of 750 ns, large X-ray detection sensitivity of 36.0 μ C mGy − 1 c m − 2 and the lowest detectable dose rate of 16 nGys −1 (40 kVp). This work will motivate new strategies to fabricate high-performance devices based on perovskites using solution-processed methods. These founding also explore a new generation of low dose and high dynamic X-ray detectors based on MHPs. Graphical Abstract: X-ray PIN photodiode with epitaxially n-type and p-type layers show extremely low dark current under large reverse bias. ga1 Highlights: We provide a solution-processed method to epitaxially grow dopant-incorporated perovskite layer. With lattice-matched epitaxial growth, the defects near the interfaces and inside the epitaxial layers are suppressed. The X-ray PIN photodiode reported in this work shows remarkable low dark current and noise current.