Yu Wenzhi, Dong Zhuo, Mu Haoran, Ren Guanghui, He Xiaoyue, Li Xiu, Lin Shenghuang, Zhang Kai, Bao Qiaoliang, Mokkapati Sudha
Department of Materials Science and Engineering, Monash University, Clayton, Victoria 3800, Australia.
Songshan Lake Materials Laboratory, Guangdong 523000, P. R. China.
ACS Nano. 2022 Aug 23;16(8):12922-12929. doi: 10.1021/acsnano.2c05278. Epub 2022 Jul 29.
Type-II Dirac semimetal platinum ditelluride (PtTe) is a promising functional material for photodetectors because of its specially tilted Dirac cones, strong light absorption, and high carrier mobilities. The stack of two-dimensional (2D) Dirac heterostructures consisting of PtTe and graphene could overcome the limit of detection range and response time occurring in the heterostructures of graphene and other low-mobility and large-gap transition metal dichalcogenides (TMDs). Here, we report an approach for achieving highly controllable, wafer-scale production of 2D Dirac heterostructures of PtTe/graphene with tunable thickness, variable size, and CMOS compatibility. More importantly, the optimized recipes achieve the exact stoichiometric ratio of 1:2 for Pt and Te elements without contaminating the underlayer graphene film. Because of the built-in electric field at the junction area, the photodetectors based on the PtTe/graphene heterostructure are self-driven with a broadband photodetection from 405 to 1850 nm. In particular, the photodetectors have a high responsivity of up to ∼0.52 AW (without bias) and a fast response time of ∼8.4 μs. Our work demonstrated an approach to synthesizing hybrid 2D Dirac heterostructures, which can be applied in the integration of on-chip, CMOS-compatible photodetectors with near-infrared detection, high sensitivity, and low energy consumption.
II型狄拉克半金属碲化铂（PtTe₂）因其特殊倾斜的狄拉克锥、强光吸收和高载流子迁移率，是一种很有前景的用于光探测器的功能材料。由PtTe₂和石墨烯组成的二维（2D）狄拉克异质结构堆叠可以克服石墨烯与其他低迁移率和大带隙过渡金属二卤化物（TMDs）异质结构中出现的探测范围和响应时间的限制。在此，我们报道了一种实现高度可控、晶圆级生产具有可调厚度、可变尺寸和CMOS兼容性的PtTe₂/石墨烯二维狄拉克异质结构的方法。更重要的是，优化后的配方实现了Pt和Te元素精确的化学计量比1:2，且不会污染下层石墨烯薄膜。由于结区的内建电场，基于PtTe₂/石墨烯异质结构的光探测器是自驱动的，具有405至1850 nm的宽带光探测能力。特别是，这些光探测器具有高达约0.52 A/W（无偏压）的高响应度和约8.4 μs的快速响应时间。我们工作展示了一种合成混合二维狄拉克异质结构的方法，其可应用于集成片上、CMOS兼容的具有近红外探测、高灵敏度和低能耗的光探测器。
