Monolithically Integrated Perovskites for High-Performance Vapor-Deposited Narrowband Photodetectors

Narrowband photodetectors, owing to their intrinsic spectral selectivity, are essential for applications such as optical communication and imaging. One strategy to preserve the high quantum efficiency of thin photodiodes is to combine them with optical filters. However, externally integrated filters increase device complexity and compromise robustness, while electrically active integrated filters generate parasitic photocurrent that limits spectral rejection. Here, we monolithically integrate an optically active but electrically passive perovskite filter within the photodetector architecture, and compare its performance with that of a conventional external filter configuration. In-depth characterization of both device designs shows that the integrated architecture preserves the performance of the active photodiode while providing narrowband operation, with a full width at half maximum (FWHM) of 50 nm at 750 nm and a specific detectivity of 1 × 10¹³ Jones at -0.5 V. Beyond its higher responsivity, the integrated device shows no observable filter degradation after three months of storage in air, in contrast to the nonintegrated configuration. These results demonstrate that monolithic integration of an electrically passive perovskite filter enables stable, high-performance narrowband photodetectors without compromising device performance.