Summary: | Fine MoS2 patterns were made at a resolution of around 150 μm with highly uniform coverage using electrohydrodynamic (EHD)-jet printing for the first time. The patterns were made using (NH4)2MoS4 precursor solution from bottom-up synthesis method. Drop-on-demand MoS2 lines from EHD jets in cone-jet mode were printed on SiO2/Si substrates, and patterning shapes with different operating parameters were investigated. Printed (NH4)2MoS4 precursor patterns were crystallized into MoS2 by a single annealing process without CVD and sulfurization. Atomic layers of printed MoS2 were controlled by the precursor concentrations in jetting. The MoS2 was used in thin-film transistors (TFTs) as an active layer and Al as source and drain electrodes for the first time. The EHD jet-printed MoS2 TFTs had a high current ratio of approximately 5.0×106, a good mobility of 19.4 cm2 V−1 s−1, a threshold voltage of 22.0 V and a subthreshold slope of 1.9 V dec−1.
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