Design and construction of ultra-thin MoSe2 nanosheet-based heterojunction for high-speed and low-noise photodetection
molybdenum diselenide, layer transition metaldichalcogenide (TMD), urtrathin nanosheet, heterojunction, ultrafast photoresponse
Advances in the photocurrent conversion of two-dimensional (2D) transitionmetal dichalcogenides have enabled the realization and application of ultrasensitiveand broad-spectral photodetectors. The requirements of previous devicesconstantly drive for complex technological implementation, resulting in limits inscale and complexity. Furthermore, the development of large-area and low-costphotodetectors would be beneficial for applications. Therefore, we demonstratea novel design of a heterojunction photodetector based on solution-processedultrathin MoSe2 nanosheets to satisfy the requirements of its application. Thephotodetector exhibits a high sensitivity to visible–near infrared light, with a lineardynamic range over 124 decibels (dB), a detectivity of ~1.2 × 1012 Jones, and noisecurrent approaching 0.1 pA·Hz–1/2 at zero bias. Significantly, the device showsan ultra-high response speed up to 30 ns with a 3-dB predicted bandwidth over32 MHz, which is far better than that of most of the 2D nanostructured andsolution-processable photodetectors reported thus far and is comparable to thatof commercial Si photodetectors. Combining our results with material-preparationmethods, together with the methodology of device fabrication presented herein,can provide a pathway for the large-area integration of low-cost, high-speedphotodetectors.
Tsinghua University Press
Xiangshun Geng,Yongqiang Yu,Xiaoli Zhou,Chunde Wang,Kewei Xu,Yan Zhang,Chunyan Wu,Li Wang,Yang Jiang,Qing Yang, Design and construction of ultra-thin MoSe2 nanosheet-based heterojunction for high-speed and low-noise photodetection. NanoRes.2016, 9(9): 2641–2651