CH₃NH₃PbBr₃ Perovskite Single-Crystal X-Ray Photon-Counting Detection Based on Multi-Layer Electrodes

Area of Science:

• Materials Science
• Solid-State Physics
• Detector Technology

Background:

• Methylammonium lead tribromide (MAPbBr₃) single crystals are promising for X/γ-ray detection.
• Developing stable electrodes for MAPbBr₃ remains a significant challenge for device performance.

Purpose of the Study:

• To investigate multi-layer electrode structures for MAPbBr₃ single crystals.
• To identify electrodes that provide Ohmic contact and low dark current for improved detector sensitivity.

Main Methods:

• Fabrication and characterization of multi-layer electrodes (Au, Au/Ti, Au/Pt/Ti).
• Current-voltage (I-V) measurements to assess electrical contact behavior.
• Kelvin force probe measurements to confirm potential contact.
• Performance evaluation using 59.5 keV monochromatic X-ray photon-counting detection and imaging.

Main Results:

• The Au/Pt/Ti electrode exhibited Ohmic contact behavior.
• Au/Pt/Ti electrodes demonstrated the lowest dark current among the tested configurations.
• Successful demonstration of 59.5 keV X-ray photon-counting detection and imaging using the optimized electrodes.

Conclusions:

• The Au/Pt/Ti multi-layer electrode is a suitable choice for stable and low-noise X/γ-ray detectors based on MAPbBr₃ single crystals.
• This research provides valuable insights for designing electrodes in lead halide perovskite optoelectronic devices.
• Optimized electrodes are crucial for advancing the application of perovskite materials in radiation detection.