Effect of Al concentration on Al-doped ZnO channels fabricated by atomic-layer deposition for top-gate oxide thin-film transistor applications PROJECT TITLE :Effect of Al concentration on Al-doped ZnO channels fabricated by atomic-layer deposition for top-gate oxide thin-film transistor applicationsABSTRACT:Al-doped ZnO (AZO) thin films were prepared by atomic layer deposition, in order to optimize their characteristics as active channel materials for oxide thin-film transistors (TFTs). The crystalline phases of the AZO films deposited at 100 °C appeared as mainly (100) planes, and their surface morphologies were homogeneous and smooth. The electrical conductivities of AZO films with varying Al concentrations were measured in-situ with a temperature sweep from 50 to 250 °C. From the conductivities, the activation energies for the carrier transport of each composition were calculated at some specified temperature ranges. A critical value of incorporated Al increased electrical conductivity by means of the donor doping effect: beyond that value, additional Al was found to act as a typical carrier suppressor. Top-gate-structured AZO TFTs were fabricated and characterized. The maximum field-effect mobility at the saturation region was found to be 0.64 cm2 V−1 s−1 when 1-at. %-Al was incorporated into the ZnO channel. Mobility showed a decreasing trend with increasing Al concentration. Negative and positive bias-stress (NBS and PBS) stabilities of the AZO-TFTs were also evaluated. The threshold voltage shifts during the NBS and PBS for 104 s were as low as −1.8 and −0.9 V, respectively. Raising the Al concentration increased the NBS instabilities, whereas the PBS stabilities were improved by higher Al concentrations. Did you like this research project? To get this research project Guidelines, Training and Code... Click Here facebook twitter google+ linkedin stumble pinterest Growth of high-density Ir nanocrystals by atomic layer deposition for nonvolatile nanocrystal memory applications