AVS 64th International Symposium & Exhibition
    Plasma Science and Technology Division Thursday Sessions
       Session PS+NS+SS+TF-ThM

Paper PS+NS+SS+TF-ThM6
Atomic Layer Etching of MoS2 for Nanodevices

Thursday, November 2, 2017, 9:40 am, Room 23

Session: Atomic Layer Etching I
Presenter: KiSeok Kim, Sungkyunkwan University, Republic of Korea
Authors: K.S. Kim, Sungkyunkwan University, Republic of Korea
K.H. Kim, Sungkyunkwan University, Republic of Korea
Y.J. Ji, Sungkyunkwan University, Republic of Korea
G.Y. Yeom, Sungkyunkwan University, Republic of Korea
Correspondent: Click to Email
Among the layered transition metal dichalcogenides (TMDs) that can form stable two-dimensional (2-D) crystal structures, molybdenum disulfide (MoS2) has been intensively investigated due to its unique properties in various electronic and optoelectronic applications with different band gap energies from 1.29 to 1.9 eV as the number of layers is decreased. To control the MoS2 layers, atomic layer etching (ALE) (which is a cyclic etching consisting of a radical-adsorption step such as Cl adsorption and a reacted-compound desorption step via a low-energy Ar+-ion exposure) can be a highly effective technique to avoid inducing damage and contamination that occur during the cyclic steps. In this study, for the MoS2 ALE, the Cl radical is used as the adsorption species and a low-energy Ar+ ion is used as the desorption species. A MoS2-ALE mechanism (by which the S(top), Mo(mid), and S(bottom) atoms are sequentially removed from the MoS2 crystal structure due to the trapped Cl atoms between the S(top) layer and the Mo(mid) layer) is reported with the results of an experiment and a simulation. A monolayer MoS2 field effect transistor (FET) fabricated after one-cycle of ALE of a bilayer MoS2 FET exhibited electrical characteristics similar to a pristine monolayer MoS2 FET indicating no electrical damage on the monolayer MoS2 surface after the ALE.