Ultrafast-Speed MoS2/CuO Photodetector Based on Strongly Coupled Heterojunction

With the wide application of van der Waals heterojunctions in optoelectronic devices, the interface coupling quality has become one of the important factors affecting the performance of heterojunction devices. Herein, a strongly coupled MoS
₂
/CuO heterojunction photodetector was obtained by adjusting the introduction order of the precursors during the plasma-enhanced atomic layer deposition (PEALD). Raman and PL spectrums analysis confirmed that the preferential deposition of oxygen precursors to form strongly coupled interfaces can achieve more efficient carrier separation. Compared with the weakly coupled devices, the strongly coupled MoS
₂
/CuO photodetector can achieve an ultrafast rise/decay time of 16/97 ns and a high responsivity of 588.5 A/W. This work provides new research strategies for the development of high-quality heterojunctions in the future.