PIN Diodes Array Made of Perovskite Single Crystal for X‐Ray Imaging

Wang, Xin; Zhao, Dewei; Qiu, Yunping; Huang, Yin; Wu, Yao Ting; Li, Guanwen; Huang, Qianqian; Khan, Qasim; Nathan, Arokia; Lei, Wei; Chen, Jing

doi:10.1002/pssr.201800380

Cited by 78 publications

(59 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[ 23,24 ] Since then, X‐ray detection using many Pb‐based perovskites has been demonstrated. [ 25–40 ] To replace the toxic Pb, X‐ray detectors employing (C 8 H 17 NH 3 ) 2 SnBr 4 , [ 41 ] Cs 2 AgBiBr 6 , [ 42–45 ] Cs 3 Bi 2 I 9 , [ 46–48 ] (NH 4 ) 3 Bi 2 I 9 , [ 49 ] (BA) 2 CsAgBiBr 7 , [ 50 ] and Cs 2 TeI 6 [ 51 ] have been reported to demonstrate good sensitivity, and most of them significantly outperform the commercial α‐Se X‐ray detectors. However, some problems such as high‐temperature preparation, a large number of crystal defects, poor uniformity, low resistivity, and high leakage current, serious ion migration and instability are still serious enough to hamper their application in devices.…”

Section: Introductionmentioning

confidence: 99%

Large Lead‐Free Perovskite Single Crystal for High‐Performance Coplanar X‐Ray Imaging Applications

Liu

Zhang

Yang

et al. 2020

Advanced Optical Materials

View full text Add to dashboard Cite

The capability to detect radiation signal like X-rays and gamma-rays has been improved dramatically in recent years. [1,2] X-ray detection is very important because of its wide range of applications in medical imaging, industrial monitoring, national security, environmental protection and remediation, and science research. In particular, flat-panel X-ray detector array is now playing an important role in in modern medical, security verification, and industrial production. [3,4] Among the materials developed for X-ray detectors, amorphous selenium (a-Se) becomes the most classic semiconductor material for direct X-ray detection (X-rays directly convert into current signals), and it is suitable for X-ray imaging because of its easy deposition process on large-scale flat-panel digital readout circuits. [5,6] Unfortunately, the conversion efficiency of a-Se is limited due to its low X-ray absorbance, caused by its low atomic number (Z = 34), accompanied by small carrier mobility and lifetime product (μτ) value of ≈10 −7 cm 2 V −1 , which leads to its very low sensitivity (440 μC Gy air −1 cm −2) even under high operating electric field (15 000 V mm −1). [7] In addition to the a-Se, many other traditional semiconductors, such as Si, [8,9] TlBr, [10,11] PbI 2 , [12,13] Ge, [14,15] HgI 2 , [16,17] CdZnTe, [18,19] and PbO, [20,21] have been well studied, and among of them, especially CdZnTe, has shown potential applications in commercial X-ray detectors. However, most of these materials either possess very high dark current and low sensitivity, or suffer from needing high-temperature (exceeding 500 °C) and complex growth equipment, let alone their high toxicity (cadmium (Cd), thallium (Tl), lead (Pb), and mercury (Hg)). Accordingly, there are still some difficulties in preparing a large area X-ray absorber layer with excellent uniformity at low temperature, limiting their application to mammography. Therefore, recently, low-temperature, solution-synthesized 60 μm thick polycrystalline methylammonium lead iodide CH 3 NH 3 PbI 3 (MAPbI 3) perovskite films have been prepared to detect 8 keV low energy X-rays with high sensitivity, and X-ray imaging was demonstrated on a photovoltaic device. [22] Later, Huang's group achieved sensitive X-ray imaging by integrating MAPbBr 3 single crystals (SCs) on a silicon substrate. [23,24] Since then, X-ray detection using many Pb-based perovskites Lead-based (Pb) perovskite recently emerged as a promising photoelectric material for direct ionization radiation detection with outstanding performance. Unfortunately, its application is limited due to its toxicity caused by high Pb content, serious ion migration, poor crystallite quality, unsatisfactory reproducibility, high resistivity, and large fluctuation of electronic properties. Herein, a better substitute of lead-free inch-sized (34.3 mm × 34.3 mm × 13.1 mm) high-quality halide (CH 3 NH 3) 3 Bi 2 I 9 single crystal (MA 3 Bi 2 I 9 SC) is presented with higher resistivity, lower ion migration, and better stability. The coplanar detector ...

show abstract

Section: Introductionmentioning

confidence: 99%

Large Lead‐Free Perovskite Single Crystal for High‐Performance Coplanar X‐Ray Imaging Applications

Liu

Zhang

Yang

et al. 2020

Advanced Optical Materials

View full text Add to dashboard Cite

show abstract

“…Hence, methylammonium lead tri‐iodide (MAPbI 3 where MA: CH 3 NH 3 ) perovskite thin films have been first investigated for X‐ray and γ‐photon direct detection and a sensitivity per unit volume of 25 μCm Gy −1 cm −3 , corresponding to a value per unit area of 1.5 μC Gy −1 cm −2 , has been demonstrated . This sensitivity is further enhanced by employing thicker films, wafers, and single crystals reaching values up to 8.4 × 10 4 μC Gy −1 cm −2 but such devices, besides mechanical stiffness, require high voltage operation that implies high power consumption, preventing wearable and portable applications. The use of thin films allows to avoid these drawbacks and to envisage the development of flexible radiation detectors extremely advantageous in many medical, civil, and wearable applications.…”

Section: Introductionmentioning

confidence: 99%

Detection of X‐Rays by Solution‐Processed Cesium‐Containing Mixed Triple Cation Perovskite Thin Films

Basiricò

Senanayak

Ciavatti

et al. 2019

Adv Funct Materials

View full text Add to dashboard Cite

Materials and technology development for designing innovative and efficient X-ray radiation detectors is of utmost importance for a wide range of applications ranging from security to medical imaging. Here, highly sensitive direct X-ray detectors based on novel cesium (Cs)-based triple cation mixed halide perovskite thin films are reported. Despite being in a thin film form, the devices exhibit a remarkably high X-ray sensitivity of (3.7 ± 0.1) µC Gy −1 cm −2 under short-circuit conditions. At a small reverse bias of 0.4 V, the sensitivity further increases by orders of magnitude reaching a record value of (97 ± 1) µC Gy −1 cm −2 which surpasses state-of-the-art inorganic large-area detectors (a-Se and poly-CZT). Based on detailed structural, electrical, and spectroscopic investigations, the exceptional sensitivity of the triple cation Cs perovskite is attributed to its high ambipolar mobility-lifetime product as well as to the formation of a pure stable perovskite phase with a low degree of energetic disorder, due to an efficient solution-based alloying of individual n-and p-type perovskite semiconductors.

show abstract

“…Electrical fields as high as ≈0.1–1 V µm −1 are commonly needed for poly‐crystalline perovskite deposits incorporated into X‐ray detectors . Large field strength requirements are in some amount lowered when devising single‐crystal approaches for X‐ray detection using perovskite materials . In any case, it is widely recognized that the application of an external bias promotes the displacement and interfacial built‐up of intrinsic mobile ions .…”

Section: Introductionmentioning

confidence: 99%

“…More sophisticated contacting materials are formed by poly(3,4‐ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) and phenyl‐C 61 ‐butyric acid methyl ester (PCBM) and ZnO as hole‐selective and electron‐selective contact and buffer layers, respectively . In any case, gold is still extensively used either in direct contact with the perovskite absorber, or covering proper interlayers . However, it is already known that Au may interact with the sensitive perovskite layers causing degradation.…”

Section: Introductionmentioning

confidence: 99%

Reversible Formation of Gold Halides in Single‐Crystal Hybrid‐Perovskite/Au Interface upon Biasing and Effect on Electronic Carrier Injection

Pospı́šil

Guerrero

Zmeškal

et al. 2019

Adv Funct Materials

View full text Add to dashboard Cite

Solar cells, light emitting diodes, and X-ray detectors based on perovskite materials often incorporate gold electrodes, either in direct or indirect contact with the perovskite compound. Chemical interactions between active layers and contacts deteriorate the operation and induce degradation, being the identification of the chemical nature of such interfacial structures an open question. Chemical reactivity of gold in contact with the perovskite semiconductor leads to reversible formation of oxidized gold halide species and explains the generation of halide vacancies in the vicinity of the interface.Electrical biasing induces contact reaction and produces modifications of the current level by favoring the ability of perovskite/Au interfaces to inject electronic carriers. The current injection increment does not depend on the halogen source used, either extrinsically by iodine vapor sublimation of Au electrodes, or intrinsically by bias-driven migration of bromide ions. In addition, the formation of a dipole-like structure at the reacted electrode that lowers the potential barrier for electronic carriers is confirmed. These findings highlight adequate selection of the external contacts and suggest the need for a deeper understanding of contact reactivity as it dominates the operation characteristics, rather than being governed by the bulk transport properties of the charge carriers, either electronic or ionic.conversion in the near future. In addition to photovoltaic applications, perovskitebased materials are being explored as sensitive layers for high-energy radiation detectors and imaging devices for medical diagnostics. [2] These detection technologies rely upon the ability of perovskite compounds of absorbing high-energy photons and convert their energy into electronic carriers that are finally collected at the outer contacts. For soft X-ray photons (<10 keV), absorbing layer thickness of tens of micrometers suffices to stop the radiation. But hard X-ray radiation (10-50 keV) possesses much longer penetration length (≈100 µm) in compounds as methylammonium lead iodide or bromide (MAPbI 3 and MAPbBr 3 ). [3] Hence, relatively thick layers (0.1-1 mm) need to be employed to achieve sufficient electrical signal. Despite the large electronic carrier mobility and mobility-lifetime product, [4,5] such thick absorbing layers should be externally biased in order to increase the detector responsivity. Electrical fields as high as ≈0.1-1 V µm −1 are commonly needed for poly-crystalline perovskite deposits incorporated into X-ray detectors. [3,5] Large field strength requirements are in some amount lowered when devising single-crystal approaches for X-ray detection using perovskite materials. [4,6] In any case, it is widely recognized that the application of an external bias promotes the displacement and interfacial built-up of intrinsic mobile ions. [7,8] Ion accumulation finally shields the electrical field within the absorbing layer bulk, reducing as a consequence the detector sensitivity. The applicability of perovs...

show abstract

PIN Diodes Array Made of Perovskite Single Crystal for X‐Ray Imaging

Cited by 78 publications

References 31 publications

Large Lead‐Free Perovskite Single Crystal for High‐Performance Coplanar X‐Ray Imaging Applications

Large Lead‐Free Perovskite Single Crystal for High‐Performance Coplanar X‐Ray Imaging Applications

Detection of X‐Rays by Solution‐Processed Cesium‐Containing Mixed Triple Cation Perovskite Thin Films

Reversible Formation of Gold Halides in Single‐Crystal Hybrid‐Perovskite/Au Interface upon Biasing and Effect on Electronic Carrier Injection

Contact Info

Product

Resources

About