| Popis: |
In this paper, a HfO2/Er2O3/HfO2 (HEH) stacked structure was developed as a gate dielectric for amorphous InGaZnO (α-IGZO) thin-film transistor (TFT) applications. Atomic force microscopy and X-ray photoelectron spectroscopy were used to study the morphological and chemical features of Er2O3 and HEH films. In comparison to the Er2O3 dielectric, the α-IGZO TFT device incorporating a HEH stacked dielectric exhibited a lower threshold voltage of 0.7 V, a higher Ion/Ioff current ratio of 2.86 × 107, a larger field-effect mobility of 15.8 cm2 V−1 s−1, and a smaller subthreshold swing of 101 mV per dec, suggesting a smooth surface at the dielectric-channel interface. Furthermore, the threshold voltage stability of α-IGZO TFT under positive gate voltage stress can be improved by using a HEH stacked structure. |
