Preferential growth of crystalline MoS2 on patterned Ni channels in contact with Au thin films

Abstract

We report selective growth of few-layered, crystalline MoS2 on Ni thin films while inhibiting growth on Au thin films and SiO2/Si when using conventional MoS2 CVD based on MoO3 and S precursors. This allows for selective growth of crystalline MoS2 with precise spatial control and repeatability across large areas with optimal precursor delivery and is critical to large-scale manufacturing of MoS2 devices. This selective growth is postulated to be due to differences in surface energy of the Ni/Au/SiO2 surfaces. Contact angle measurements show that Ni thin films have a lower contact angle and are more hydrophilic than Au or SiO2. Previous studies have shown that low concentrations of Ni result in formation of larger grains of MoS2, aiding the growth of MoS2 on patterned Ni channels. Ongoing work explores the possibility of selectively etching the underlying Ni thin films to use these patterned Au/MoS2 thin films as FET devices.