Sulfurization Engineering of One-Step Low-Temperature MoS2 and WS2 Thin Films for Memristor Device Applications

2D materials have been of considerable interest as new materials for device applications. Non-volatile resistive switching applications of MoS2 and WS2 have been previously demonstrated; however, these applications are dramatically limited by high temperatures and extended times needed for the large-area synthesis of 2D materials on crystalline substrates. The experimental results demonstrate a one-step sulfurization method to synthesize MoS2 and WS2 at 550 degrees C in 15 min on sapphire wafers. Furthermore, a large area transfer of the synthesized thin films to SiO2/Si substrates is achieved. Following this, MoS2 and WS2 memristors are fabricated that exhibit stable non-volatile switching and a satisfactory large on/off current ratio (10(3)-10(5)) with good uniformity. Tuning the sulfurization parameters (temperature and metal precursor thickness) is found to be a straightforward and effective strategy to improve the performance of the memristors. The demonstration of large-scale MoS2 and WS2 memristors with a one-step low-temperature sulfurization method with simple strategy to tuning can lead to potential applications such as flexible memory and neuromorphic computing.

Automated summary

The research demonstrated successful synthesis of MoS2 and WS2 on sapphire wafers through a one-step sulfurization method, with the thin films transferred to SiO2/Si substrates. The fabricated MoS2 and WS2 memristors showed stable non-volatile switching and a satisfactory large on/off current ratio. Tuning the sulfurization parameters was found to be a simple and effective strategy to improve the performance of the memristors.