We have explored the effect of post-annealing on the electrical properties of an indium gallium zinc oxide (IGZO) transistor with an Al2O3 bottom gate dielectric, formed by a sol–gel process. The post-annealed IGZO device demonstrated improved electrical performance in terms of threshold variation, on/off ratio, subthreshold swing, and mobility compared to the non-annealed reference device. Capacitance–voltage measurement confirmed that annealing can lead to enhanced capacitance properties due to reduced charge trapping. Depth profile analysis using X-ray photoelectron spectroscopy proved that percentage of both the oxygen vacancy (VO) and the hydroxyl groups (M–OH) within the IGZO/Al2O3 layers, which serve as a charge trapping source, can be substantially reduced by annealing the fabricated transistor device. Furthermore, the undesired degradation of the contact interface between source/drain electrode and the channel, which mainly concerns VO, can be largely prevented by post-annealing. Thus, the facile annealing process also improves the electrical bias stress stability. This simple post annealing approach provides a strategy for realising better performance and reliability of the solid sol–gel oxide transistor.

中文翻译：

---

通过后退火实现具有高k Al2O3栅极电介质的溶胶-凝胶IGZO晶体管的改进电性能。

我们已经研究了后退火对通过溶胶-凝胶工艺形成的具有Al2O3底栅电介质的铟镓锌氧化物（IGZO）晶体管的电性能的影响。与未退火的参考设备相比，后退火的IGZO器件在阈值变化，开/关比，亚阈值摆幅和迁移率方面显示出改善的电气性能。电容电压测量结果表明，退火可以通过减少电荷俘获来提高电容性能。使用X射线光电子能谱进行的深度剖面分析证明，作为电荷俘获源的IGZO / Al2O3层中的氧空位（VO）和羟基（M–OH）的百分比可以通过退火显着降低制成的晶体管器件。此外，通过后退火可以在很大程度上防止源/漏电极与沟道之间的接触界面的不期望的劣化，该劣化主要涉及VO。因此，容易的退火工艺也提高了电偏置应力的稳定性。这种简单的后退火方法为实现固态溶胶-凝胶氧化物晶体管的更好性能和可靠性提供了一种策略。