Low‐Temperature Melt Processing Monolithic Integration of Organic Manganese (II) Bromide Wafers with Pixelated Substrate for High Sensitivity X‐Ray Imaging

Abstract Environmentally‐friendly metal halides have become emerging candidates for X‐ray imaging applications. However, it remains challenging to obtain noise and ion migration suppressed crystal structures. More seriously, integration with mature circuits in an easy‐to‐implement manner is a huge obstacle to commercialization. Here, a 0D structure‐based benzyltrimethylammonium manganese bromide (BTA₂MnBr₄, BTA: C₁₀H₁₆N) is reported. Further studies point out that such structure exhibits obvious quantum confinement effects, providing large bandgap (3.20 eV) and exciton activation energy (≈115 meV) with decreasing thermal noise, and large activation energy for ionic transport (≈0.37 eV) with limited ion migration. Then, the BTA₂MnBr₄ wafer is fabricated via solvent‐free, scalable, and low‐temperature (175 °C) melt processing technology. The obtained wafer shows highly crystalline and good densification that can effectively collect the generated charges, which avoids the compound losses and further limits the ion migration. As a result, the related X‐ray detector demonstrates high sensitivity of 5.56 × 10³ µC Gy_air⁻¹ cm⁻², a low detection limit of 8.7 nGy_air s⁻¹, fast response (≈10 ms), high‐spatial resolution (≈4.1 lp mm⁻¹), good stability, and imaging capability. Moreover, the integration of the wafer with pixelated electrode substrate is also successfully achieved, applied, and validated with strong mechanical connection and reliable contact.