ZnO-Based Low-Voltage Inverter With Quantum-Well-Structured Nanohybrid Dielectric

We report on the fabrication of 2-V-operating ZnO-based inverter with two n-channel thin-film transistors (TFTs) on 22-nm-thin organic/inorganic nanohybrid dielectric, which contains AlO_x/TiO_x/AlO_x in triple-layer structure. The inverter shows a high voltage gain of ~20 under the supply voltage (V_DD) of 2 V but with a marginal transition voltage of 0.1 V (operation range of 0-2 V). To control the transition voltage to a more adequate value, an 8-V gate pulse was applied on driving ZnO-TFT so that some of the channel electrons would be tunneled through the AlO_x-based barrier and trapped in the TiO_x-based layer. Our inverter then displayed an optimum transition voltage of 0.75 V.