Enhanced Electrical Properties of Metal-Organic Chemical Vapor Deposition-Grown MoS2 Thin Films through Oxygen-Assisted Defect Control

Abstract

Although the synthesis of MoS2 thin film with a large area and excellent uniformity has been achieved through advanced synthesis techniques, such as metal-organic chemical vapor deposition (MOCVD), intrinsic defects such as vacancies and grain boundaries which degrade electrical performance still inevitably result from the process. In this paper, a method for controlling intrinsic defects in MOCVD-grown MoS2 thin film to achieve enhanced electrical performance is reported. After applying the defect-control process, high-resolution transmission electron microscopy confirms that the MoS2 thin film maintains a hexagonal lattice structure without any destruction or distortion, indicating that this is a nondestructive method. In addition, the MoS2 thin film subjected to the defect-control process exhibits enhanced n-type characteristics in the photoluminescence and ultraviolet photoelectron spectroscopy analyses. Field-effect transistors using the defect-controlled MoS2 as the channel also show enhanced electrical performance, arising from reductions in sheet and contact resistances of 21% and 46%, respectively. This improvement in the resistances leads to an increase in field-effect mobility from 3.2 up to 11.8 cm(2) V-1 s(-1).