Research Of KH550-GO Composite Dielectrics Low Voltage Oxide Thin Film Transistor

In recent years, the low-voltage oxide thin film transistor(TFT) has attracted wide spread attention because of its high field-effect mobility, good light transmission and easy production of large area. However, due to the traditional gate dielectric material with low dielectric constant, when the operating voltage of device is low, the grid voltage is difficult to control channel current, which greatly limits the application of TFT device in low power consumption and high-performance electronic products. To increase the gate dielectric capacitance coupling characteristics, reduce the operating voltage and improve device electrical characteristics, it is started to reduce the thickness of gate dielectric film and explore the new gate dielectric materials. But lower gate dielectric film thickness is often limited by process requires and the film strength and performance will decrease, which may add a certain hidden trouble about electrical properties and the structure design of TFT devices. To reduce the operating voltage and ensure the electrical characteristics of TFT devices, more and more researchers devoted to research the new gate dielectric materials.(1) Due to the molecular structure of KH550 containing lots of-NH2 and-Si-O-C2H5 bonds,-Si-O-C2H5 hydrolysis easily generate Si-OH bonds, and-OH and-NH2 belong to hydrophilic groups, we predict that KH550 solid electrolyte film is an ideal gate dielectric material of low-voltage oxide thin film transistors. However, as we have all known, there are no reports on the protonic conductivities for KH550 and the KH550 gated thin-film transistors. Therefore, we use the KH550 solid electrolyte as TFT device gate dielectric materials and measure the various properties of KH550 film. What’s more, the electrical characteristics of KH550-TFT devices were tested to analyze KH550 solid electrolyte could be become the ideal materials of thin film transistor gate dielectric.(2) Spin coated-processed Silane Coupling Agents(KH550-GO) composite proton conductor film shows a large specific gate capacitance of 2.18 μF/cm2 due to the interfacial electric-double-layer effect. Low-voltage oxide(IZO) TFTs gated by a KH550-GO composite proton conductor film were self-assembled by only one shadow-mask. Electrical characteristics of the devices were measured by a Keithley 4200 SCS semiconductor parameter analyzer at room temperature under the condition of darkness.The results showed that KH550- GO oxide thin film transistors possess good electrical properties, the operating voltage is only 2 V, the saturation current, subthreshold gate voltage swing,current on/off ratio, and field-effect mobility are estimated to be 580 μA, 108 mV/dec,4×107, and 16.7 cm2·V-1·s-1, respectively.In conclusion, the reports of the KH550-GO solid electrolyte gated IZO-TFT with good performance would enrich its application for low power device, portable devices and good performance devices.