Flexible Soft X‐Ray Image Sensors based on Metal Halide Perovskites With High Quantum Efficiency

Soft X‐ray imaging is a powerful tool to explore the structure of cells, probe material with nanometer resolution, and investigate the energetic phenomena in the universe. Conventional soft X‐ray image sensors are by and large Si‐based charge coupled devices that suffer from low frame rates, complex fabrication processes, mechanical inflexibility, and required cooling below −60 °C. Here, a soft X‐ray photodiode is reported based on low‐cost metal halide perovskite with comparable performance to commercial Si‐based device. Nanothrough network electrode minimized the optical loss due to the shadowing of insensitive layers, while a multidimensional perovskite heterojunction is generated to reduce the photo‐generated carrier loss. This strategy promoted a record quantum efficiency of 8 × 103% without cooling, several orders of magnitude greater than the previously achieved. Flexible and curved soft X‐ray imaging arrays are fabricated based on this high‐performance device structure, demonstrating stable soft X‐ray response and sharp imaging capabilities. This work highlights the low‐cost and efficient perovskite photodiode as a strong candidate for the next‐generation soft X‐ray image sensors. With nanothrough network electrode and multidimensional perovskite heterojunction to reduce the photon and carrier loss respectively, this work demonstrates the highest quantum efficiency of perovskite‐based soft X‐ray photodetectors. The devices also show excellent stability under long‐term soft X‐ray radiation and extreme temperatures (10 to 383 K), possessing great potential to serve as pixels of next‐generation curved soft X‐ray image sensor.