Area‐Selective Atomic Layer Deposition of MoS2 using Simultaneous Deposition and Etching Characteristics of MoCl5

Abstract

A novel selective atomic layer deposition (ALD) process for depositing MoS2 using MoCl5 and H2S precursors is proposed. On the surface of SiO2, the prolonged introduction of MoCl5 vapor by increasing the MoCl5 pulsing time rapidly suppresses the subsequent MoS2 growth due to the intense self‐etching effect of MoCl5, that is, the detachment of weakly bonded surface adsorbates (MoClx*). In contrast, the surface of Al allows more facile adsorption of MoCl5 than in the case of the SiO2 surface, and thus effectively compensates for the reduced deposition rate. By optimizing the MoCl5 pulsing time, the self‐aligned growth of MoS2 on predefined Al (5 nm) patterns (circular and letter patterns) on a SiO2 substrate with a negligible selectivity loss is demonstrated.