Chemical vapor deposition-free solution-processed synthesis method for two-dimensional MoS2 atomic layer films.

In this study, a solution-processed synthesis method was developed and successfully synthesized large-scale and uniform MoS2 thin films without using chemical vapor deposition. The MoS2 precursor solution was formulated by a sulfur-dissolving method to obtain uniform coating properties. MoS2 thin film was prepared by simple spin-coating and a one-step annealing method. The solution-synthesized MoS2 thin films were characterized to examine the 2H MoS2 structure. The various atomic layers could be controlled with the precursor concentrations. For example, two layers were obtained with 0.0070 M, three layers were obtained with 0.0125 M, and five layers were obtained with 0.025 M of MoS2 in the precursor solution, which were confirmed by scanning transmission electron microscopy.

A mixed solution-processed gate dielectric for zinc-tin oxide thin-film transistor and its MIS capacitance.

Solution-processed gate dielectrics were fabricated with the combined ZrO2 and Al2O3 (ZAO) in the form of mixed and stacked types for oxide thin film transistors (TFTs). ZAO thin films prepared with double coatings for solid gate dielectrics were characterized by analytical tools. For the first time, the capacitance of the oxide semiconductor was extracted from the capacitance-voltage properties of the zinc-tin oxide (ZTO) TFTs with the combined ZAO dielectrics by using the proposed metal-insulator-semiconductor (MIS) structure model. The capacitance evolution of the semiconductor from the TFT model structure described well the threshold voltage shift observed in the ZTO TFT with the ZAO (1:2) gate dielectric. The electrical properties of the ZTO TFT with a ZAO (1:2) gate dielectric showed low voltage driving with a field effect mobility of 37.01 cm(2)/Vs, a threshold voltage of 2.00 V, an on-to-off current ratio of 1.46 × 10(5), and a subthreshold slope of 0.10 V/dec.

Materials and optimized designs for human-machine interfaces via epidermal electronics.

Thin, soft, and elastic electronics with physical properties well matched to the epidermis can be conformally and robustly integrated with the skin. Materials and optimized designs for such devices are presented for surface electromyography (sEMG). The findings enable sEMG from wide ranging areas of the body. The measurements have quality sufficient for advanced forms of human-machine interface.

Inkjet-printed In(2)O(3) thin-film transistor below 200 °C.

High-performance In2O3 thin-film transistors could be prepared by an inkjet-printing method below 200 °C with a single precursor and solvent formulation. The self-combustion reaction took place with the electrical properties of In2O3 at a low temperature of 147 °C, which was confirmed by X-ray photoelectron spectroacopy and thermal analysis. The electrical properties after postannealing at 200 °C were as follows: a mobility of 3.98 cm(2)/V·s, a threshold voltage of 1.83 V, a subthreshold slope of 0.4 V/dec, and an on-to-off current ratio of 10(8), which are the best properties by an inkjet process thus far. The positive bias stability was much improved by postannealing, and good negative bias stability was obtained.