Self‐Powered Solar‐Blind Polarization‐Sensitive β‐Ga ₂ O ₃ Photodetector Focal Plane Array

ABSTRACT Polarization‐sensitive solar‐blind ultraviolet SBUV photodetectors, resolving light intensity, wavelength and polarization, are critical for flame detection, ozone monitoring and high‐contrast imaging. However, fabricating polarizer‐free, miniaturized, low‐power real‐time imaging devices remains challenging, as miniaturization and polarizer removal inevitably compromise polarization performance and spatial resolution. β‐Ga 2 O 3 is an ideal material for its ultra‐wide bandgap (4.7–4.9 eV) that suppresses solar background noise and intrinsic anisotropy enabling polarizer‐free polarization‐sensitive photodetection. Herein, a solar‐blind polarization‐sensitive β‐Ga 2 O 3 photodetector focal plane array is fabricated by leveraging the anisotropic crystal structure of its (100) and (001) facets. The asymmetric electrode design is rationally employed to construct a Schottky barrier, which endows the array with self‐powered photodetection capability. The array exhibits a high polarization ratio (PR = 4.7), ultralow dark current (<1 pA) and fast response (4 ms/20 ms rise/fall time), enabling real‐time polarization‐resolved imaging of target letters via a custom readout circuit. A CNN dual‐label recognition model achieves over 95% accuracy in letter and polarization angle identification. This work verifies the polarization response of β‐Ga 2 O 3 dependent on crystal facets, realizes synergistic optimization of key performances for miniaturized devices, and lays a reliable material and technical foundation for high‐performance SBUV polarization imaging systems.