| AVS 63rd International Symposium & Exhibition | |
| Scanning Probe Microscopy Focus Topic | Wednesday Sessions |
| Session SP+SS+TF-WeM |
| Session: | Probing Electronic Properties |
| Presenter: | Irma Kuljanishvili, Saint Louis University |
| Authors: | R. Dong, Saint Louis University L. Moore, Saint Louis University N. Aripova, Saint Louis University C. Williamson, Saint Louis University R. Schurz, Saint Louis University L.E. Ocola, Argonne National Laboratory I. Kuljanishvili, Saint Louis University |
| Correspondent: | Click to Email |
Advances in graphene research ignited interest in other type of two-dimensional (2D) atomic crystals, such as hexagonal boron nitride and layered transition metal dichalcogenides (TMDCs). Among these new types of 2D materials, the applications of TMDCs in logic electronics and optoelectronics are promising because of their sizable bandgaps and natural stability. The techniques which enable heterostructure formation with different TMDCs systems have provided further solution to the design of high performance electronic devices such as those for photovoltaics and optoelectronics. The existing heterostructures fabrication methods, based on mechanical exfoliation and/or wet chemical transferring rely on traditional fabrication methods such as photo-and e-beam lithography.
To realize the selective growth and layered assembly of heterostructures at predefined location, here, we report on application of mask free, scanning probe based direct writing method. With the use of AFM cantilevers and developed water based “inks”, we demonstrate arrays of MoS2 and WS2 dots and ribbon arrays at predefined locations on variety of substrates. Employing this SPM based patterning method we have also fabricated MoS2/WS2 heterostructures of sub-micrometer scales in a controlled fashion. The quality of MoS2/WS2 heterostructures was confirmed by Raman spectroscopy, AFM characterization and electrical transport measurements. Our mask free nanolithography approach offers an alternative route for patterning and growth of TMDCs with added benefit of potential reduced contamination of the TMDCs surfaces and interfaces between materials and substrates. It demonstrates a promising unconventional technology for fabrication of high quality TMDCs heterostructures in convenient manner capable of nanoscale precision.
Acknowledgements
Use of the Center for Nanoscale Materials was supported by the U. S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02 06CH11357. I.K. acknowledges support of NSF MRI program (Award No. 1338021), and the Saint Louis University seed funds.