Template directed perovskite X-ray detectors towards low ionic migration and low interpixel cross talking

Area of Science:

• Materials Science
• Detector Physics

Background:

• Metal halide perovskites offer high performance for direct X-ray detection due to strong absorption and long carrier lifetimes.
• Ionic migration and charge sharing in perovskites degrade spatial resolution in imaging applications.

Purpose of the Study:

• To develop a novel method for growing CsPbBr2I thick films for direct X-ray detection.
• To mitigate ionic migration and charge sharing effects in perovskite X-ray detectors.

Main Methods:

• Utilizing porous anodic aluminum oxides (AAO) as a template for CsPbBr2I film growth.
• Investigating the impact of oxygen passivation on ionic migration activation energy.
• Evaluating charge diffusion across a 10 μm pixel pitch.

Main Results:

• AAO template facilitates CsPbBr2I thick film growth for X-ray detection.
• Oxygen passivation increased ionic migration activation energy to 0.701 eV.
• Achieved a low dark current drift of 1.01 × 10^-5 nA cm^-1s^-1V^-1.
• AAO walls effectively suppressed charge diffusion at 10 μm pixel pitch.

Conclusions:

• Porous AAO templates provide a new route for high-resolution perovskite X-ray detectors.
• Reduced ionic migration and charge crosstalk bring perovskite detectors closer to practical use.
• This approach enhances the viability of perovskite-based direct X-ray imaging.