Local Ion Beam Modification of Materials Enables Atomically Thin Circuits

Local Ion Beam Modification of Materials Enables Atomically Thin Circuits

Scientific Achievement

Helium ion beam manipulation is used to tune the transport behavior in a single layer material, leading to atomically thin circuits.

Significance and Impact

Atomically thin circuits will enable next-generation electronics and optoelectronics.

Research Details

– Selective sputtering in a helium ion microscope locally changes the conduction mechanism in exposed single layers of tungsten diselenide (WSe2) and tungsten disulfide (WS2).
– Scanning transmission electron microscopy combined with electron energy loss spectroscopy and advanced image analysis shows preferential sputtering of selenium.
– First-principle calculations confirm a semiconductor-to-metallic transition induced by pore and edge effects.
– Complete inverters and transistors with an on/off ratio of 106 are achieved in atomically thin circuits.
Image Caption:  

(a) Edge contact field effect transistor (FET) in which source and drain contacts consist of modified regions of the single-layer material.
(b) Intensity map of the Raman 2LA(M) peak overlaid on an optical micrograph of a WS
2 layer locally exposed to different ion doses.

M.G. Stanford, P. R. Pudasaini, E. T. Gallmeier, N. Cross, L. Liang, A Oyedele, G. Duscher, M. Mahjouri-Samani, K. Wang, K. Xiao, D. B. Geohegan, A. Belianinov, B. G. Sumpter, and P. D. Rack, "High conduction hopping behavior induced in transmission metal dichalcogenides by percolating defect networks:  toward atomically thin circuits," Adv. Funct. Mater. (2017). DOI: 10.1002/adfm.201702829

CNMS Researchers