High-Performance Self-Powered Ultraviolet Photodetector Based on NiO/La-Doped SrSnO3/Nb-Doped SrTiO3 Dual-Heterojunction

en This link goes to a English section zh This link goes to a Chinese section The development of high-performance photodetectors critically relies on innovative interfacial band engineering, a strategy that enables the synergistic enhancement of photocurrent and drastic suppression of dark current. Herein, a self-powered ultraviolet (UV) photodetector is demonstrated based on a NiO/La-doped SrSnO 3 (LSSO)/Nb-doped SrTiO 3 (NSTO) dual heterojunction. Benefiting from the reinforced interfacial potential barriers and multiple built-in electric fields at both the NiO/LSSO and LSSO/NSTO interfaces, the device achieves highly efficient charge separation while effectively inhibiting carrier leakage in the dark. Consequently, the photodetector exhibits an ultra-low dark current of 0.18 pA at zero bias. Under 254 nm UV illumination, the device delivers a high responsivity of 41.81 mA W −1 , a specific detectivity of 7.87 × 10 12 Jones, a photocurrent-to-dark-current ratio as high as 4.4 × 10 4 , and rapid response times (rise/fall) of 2.89/13.93 ms. These results underscore the advantages of the dual-heterojunction architecture in boosting photoelectric conversion efficiency and suppressing noise, thereby providing a robust strategy for high-performance, oxide-based self-powered UV photodetection. 摘要 en This link goes to a English section zh This link goes to a Chinese section 高性能光电探测器的研发关键在于创新性的界面能带工程,该策略能够协同增强光生电流并显著抑制暗电流。本文报道了一种基于NiO/La:SrSnO 3 (LSSO)/Nb:SrTiO 3 (NSTO)双异质结结构的自供电紫外光电探测器。得益于NiO/LSSO和LSSO/NSTO界面处增强的界面势垒和多重内置电场,该器件在有效抑制暗态下载流子泄漏的同时,实现了高效的电荷分离。结果表明,该探测器在零偏压下表现出0.18 pA的极低暗电流。在254 nm紫外光照射下,器件的响应度达到41.81 mA W −1 、探测率为7.87 × 10 12 Jones,光暗电流比高达4.4 × 10 4 ,并具备2.89/13.93 ms (上升/下降时间)的快速响应特性。上述结果充分表明,双异质结结构在提升光电转换效率和抑制噪声方面具有显著优势,为构建高性能氧化物自供能紫外光电探测器提供了一种有效的设计策略。