Stacked printed MoS2 and Ag electrodes using electrohydrodynamic jet printing for thin-film transistors

Transition metal dichalcogenide-based thin-film transistors (TFTs) have drawn intense research attention, but they suffer from high cost of materials and complex methods. Directly printed transistors have been in the limelight due to low cost and an environmentally friendly technique. An electrohydrodynamic (EHD) jet printing technique was employed to pattern both MoS2 active layer and Ag source and drain (S/D) electrodes. Printed MoS2 lines were patterned on a silicon wafer using a precursor solution and simple annealing, and the patterns were transferred on other SiO2 substrates for TFT fabrication. On top of the patterned MoS2, Ag paste was also patterned for S/D electrodes using EHD jet printing. The printed TFTs had a high on-off current ratio exceeding 10(5), low subthreshold slope, and better hysteresis behavior after transferring MoS2 patterns. This result could be important for practical TFT applications and could be extended to other 2D materials.