Self-Powered Photodetectors Based on InGaN/PdO PN Heterojunctions for Visible Light Communication

InGaN-based self-powered photodetectors (PDs) are promising for visible light communication (VLC) due to their high efficiency in detecting visible light without external power supply. However, they still face the challenge of poor self-powered performance due to the inherent crystal quality issues of InGaN. In this regard, through the effective design of the heterojunctions structure, InGaN/PdO PN heterojunctions self-powered PDs have been fabricated. The combination of InGaN and PdO creates a high-quality unintentionally doped PN type II heterojunction, and generates a built-in electric field, leading to efficient natural separation of photogenerated carriers. The as-prepared PD reveals a high responsivity of 893.9 mA/W and a specific detectivity of
$1.0\times 10^{{13}}$
jones in the visible band of 450 nm at zero bias voltage. Moreover, it also presents a high light-to-dark current ratio of
$8\times 10^{{3}}$
and a short rise/decay time of 2.43/3.14 ms, respectively. Coupled with the reveals excellent stability with no degradation in air conditions for up to 3 months, makes it promising for the realization of low power passive VLC.