Controlled growth of MoS₂ by atomic layer deposition on patterned gold pads

Approaches to synthesize large-area MoS₂ thin films have been extensively investigated in recent years towards system-level micro-/nanoelectronics applications. Methods including chemical vapor deposition (CVD) and atomic layer deposition (ALD) can enable uniform and wafer-scale MoS₂ films on insulating substrates, but without selective control on the growth location. Herein, we report a controlled growth of ultra-thin MoS₂ films on Au pads patterned on insulating substrates using ALD-based techniques. Clear difference in the incubation period duration of the ALD process among different substrate surfaces has been observed. Selective growth of MoS₂ can be achieved on patterned Au on SiO₂/Si substrate while the incubation period is shorter on sapphire substrate as compared with that on SiO₂/Si. In addition, the influence of deposition temperature on the film growth dynamics on difference surfaces has been studied. Such controlled growth of MoS₂ by ALD can be very attractive in future optoelectronics applications and the synthesis on patterned Au is promising in fulfilling its application potentials such as electrocatalyst in hydrogen evolution reaction.