| Popis: |
Single-crystal, one-dimensional (1-D), metal-oxide nanostructures are well known for their excellent electronic transport properties. Moreover, metal oxide-nanowire field-effect transistors (FETs) offer both high optical transparency and large mechanical conformability which are essential for flexible and transparent display applications. While the “on-currents” achieved with nanowire channel transistors are already sufficient to drive active-matrix organic light-emitting diode (AMOLED) displays; it is shown here in addition that application of electrochemical-gating (EG) to nanowire electronics reduces the operation voltage to ≤2 V. This opens up new possibilities for the realization of flexible, portable, transparent displays that can be powered by thin film batteries. Electrolyte gated field-effect transistors are fabricated with single crystalline metal oxide nanowires such as ZnO and SnO2 as the channel and a composite solid polymer electrolyte (CSPE) is used as dielectric gating material. Excellent transistor performance and a very low-voltage operation (≤ 2 V) have been demonstrated. Practical use of such electrolyte-gated field-effect transistor (EG FET) devices is validated by their long-term stability in air. Moreover, due to the good conductivity (≈10−2 S/cm) of the CSPE, sufficiently high switching speed of such EG FETs is attainable; a cut-off frequency in excess of 100 kHz is measured for in-plane FETs. Furthermore, thermal stability of the FETs is systematically examined up to 180 °C. Unchanged transistor characteristics are obtained up to 70 °C, short exposure at 110 °C is found acceptable, making such devices compatible with organic photovoltaics or various biomedical applications. Additionally, the solid polymer electrolyte developed in this study has great potential for future device fabrication using all-solution processed and high throughput techniques. |
