Effect of Hydrogen on Long-Term Reliability of InZnO TFTs Characterized by Low-Frequency Noise

The long-term reliability of InZnO (IZO) thin film transistors (TFTs) under a hydrogen-containing environment is researched. Hydrogen incorporation induces hydroxyl groups and oxygen vacancies, leading to the generation of electrons and extra random trap/emission processes in the IZO films. Consequently, the electrical properties and low frequency noise characteristics of IZO TFTs are deteriorated under the long-term hydrogen treatment. Additionally, the recovery characteristics of IZO TFTs after the hydrogen treatment demonstrate that the hydrogen induced hydroxyl groups and oxygen vacancies remain stable at room temperature. The oxygen vacancies can be eliminated, while the hydroxyl groups may still exist at a high temperature. These results may provide useful guidelines in the design and application of IZO TFTs.