中国物理B ›› 2025, Vol. 34 ›› Issue (12): 128501-128501.doi: 10.1088/1674-1056/adea9d
Zhichao Chen(陈志超)1, Feng Ji(季枫)1, Yadan Li(李亚丹)1, Yahan Wang(王雅涵)1, Xuehao Ge(葛薛豪)1, Kai Jiang(姜凯)1, Hai Zhu(朱海)2, and Xianghu Wang(王相虎)1
Zhichao Chen(陈志超)1, Feng Ji(季枫)1, Yadan Li(李亚丹)1, Yahan Wang(王雅涵)1, Xuehao Ge(葛薛豪)1, Kai Jiang(姜凯)1, Hai Zhu(朱海)2, and Xianghu Wang(王相虎)1
摘要: The development of high-performance dual-band photodetectors (PDs) capable of simultaneous deep ultraviolet (DUV) and infrared (IR) detection is critical for advanced optoelectronic applications, particularly in missile warning and target identification systems. Conventional UV/IR PDs often suffer from UV (320-400~nm) noise interference and limited responsivity due to the use of narrow-bandgap semiconductors and self-powered operation modes. To address these challenges, high-quality $\beta$-Ga$_{2}$O$_{3}$ thin films were epitaxially grown on c-plane sapphire via metalorganic chemical vapor deposition (MOCVD), exhibiting excellent crystallinity and surface morphology. Unlike conventional heterojunctions ($\beta$-Ga$_{2}$O$_{3}$/graphene or $\beta$-Ga$_{2}$O$_{3}$/TMDs), the $\beta$-Ga$_{2}$O$_{3}$/BP structure leverages BP's tunable bandgap and high carrier mobility while maintaining strong type-II band alignment, thereby facilitating efficient charge separation under both UV and IR illumination. We present a high-sensitivity dual-band PD based on a $\beta$-Ga$_{2}$O$_{3}$/black phosphorus (BP) pn heterojunction. The ultrawide bandgap of $\beta$-Ga$_{2}$O$_{3}$ enables selective detection of DUV light while effectively suppressing interference from long-wave ultraviolet (UVA, 320-400 nm), whereas BP provides a layer-dependent infrared (IR) response. Photocurrent analysis reveals distinct carrier transport mechanisms, with electrons dominating under UV illumination and holes contributing predominantly under IR exposure. A systematic investigation of the bias-dependent photoresponse demonstrates that the responsivity increases significantly at higher voltages. Under a 7 V bias, the device exhibits a high responsivity of $4.63 \times 10^{-2}$ $\rm{mA/W}$ at 254 nm and $2.35 \times 10^{-3}$ $\rm{mA/W}$ at 850 nm. This work not only provides a viable strategy for developing high-performance dual-band PDs but also advances the understanding of heterojunction-based optoelectronic devices for military and sensing applications.
中图分类号: (Photodetectors (including infrared and CCD detectors))