Laser-Direct-Written Surface Structure on a MAPbI₃ Single-Crystal Sheet to Enhance Near-Infrared Photodetection Performance

Perovskite single-crystal sheets (SC-Sheets) stand out in planar integration, surface structural engineering, and superior charge-carrier transport dynamics, solidifying their status as a leading platform for high-performance perovskite optoelectronics. This work presents a laser-direct-writing-enabled fabrication of periodic high-aspect-ratio ridge arrays on MAPbI 3 SC-Sheets. Each engineered ridge operates as a Fabry-Pérot resonator, selectively amplifying near-infrared (NIR) detection sensitivity at target wavelengths through resonance cavity modulation. For devices optimized at 1064 nm, this architecture achieves a responsivity of 241.2 mA/W, On/Off ratio of 2.6 × 10 4, detectivity of 7.6 × 10 10 Jones, and 28.15% external quantum efficiency, representing 2 orders of magnitude improvement over pristine devices while rivaling single-photon detection thresholds. Critically, laser-induced surface defects exhibit negligible impact on bulk-phase NIR photoresponse within the single-crystal matrix, validating the methodology’s robustness. The technique further demonstrates exceptional scalability and process simplicity, emerging as a manufacturable paradigm for next-generation NIR photodetector industrialization.