Ultralow-dose X-ray imaging enabled by vertically homogeneous perovskite films

Area of Science:

• Materials Science
• Medical Imaging
• Detector Physics

Background:

• Artificial intelligence drives demand for advanced imaging detectors, especially for low-photon-flux applications like low-dose X-ray imaging.
• Conventional detectors struggle with sparse photon statistics and material instabilities, leading to amplified noise and reduced image quality at ultralow doses.

Purpose of the Study:

• To address the materials-to-electronics bottleneck in ultralow photon flux detection.
• To develop a novel fabrication method for perovskite films that enhances detector performance.

Main Methods:

• A new liquid-phase growth and annealing strategy was employed for perovskite film crystallization.
• This method eliminates thermal and mass-transport instabilities common in conventional techniques.
• The resulting films exhibit exceptional vertical uniformity for depth-independent charge collection.

Main Results:

• Achieved a 10-fold reduction in image noise due to minimized stochastic fluctuations.
• Demonstrated high-quality X-ray imaging at an ultralow effective per-pixel dose of 40.6 nGy_air.
• Enabled depth-independent charge collection, improving detector reliability.

Conclusions:

• The novel perovskite fabrication method overcomes previous limitations in ultralow photon flux detection.
• The developed detectors set a new benchmark for safe and high-quality clinical X-ray imaging.
• This advancement holds significant potential for AI-driven quantitative imaging across various regimes.