Patterned Photoluminescence in Gr/MoS2 heterostructure using a contact mode atomic force microscope
Chak Ming Liu1*, W.H Chang1, W.C Lin1
1物理系, 國立師範大學, 台北市, Taiwan
* Presenter:Chak Ming Liu,
In this study, it has been proven that the AFM tip cleans PMMA and graphene ruptured by contact force. The graphene transfer on MoS2 used the wet method. Gr/MoS2 is rubbed by the tip of AFM in a 10*10 μm area, and the contact force is tuned from 110 to 660nN. Graphene is easily torn by a contact force exceeding 220nN, as shown in the optical image. After the transfer process, the photoluminescence intensity ratio of MoS2 is reduced by about 97% and a redshift occurs. After the rubbing process, the photoluminescence intensity of MoS2 tends to return to the original, because the graphene coverage breaks as the contact force increases. Optical images, PL mapping, and KPFM are used for the characterization of the graphene surface rubbed by the AFM tip. Finally, the graphene layer could be patterned by AFM tip lithography, and then 660nN cracked to expose the 4*4 μm MoS2 area. As a result, cracked graphene can be used to create different structures to develop unique multilayer-2D material devices.

Keywords: Patterned, heterostructure, contact mode atomic force microscope, rubbed, Photoluminescence