Correlation between the stability and trap parameters of amorphous oxide thin film transistors

We report on the temperature dependence phenomena in stability and trap related parameters in amorphous-hafnium–indium–zinc-oxide (a-HIZO) thin film transistors (TFTs) with different Hf-ratio. The optimized 7HIZO TFT shows large μFE of >11.1 cm2/V s and good stability based in large falling-rate (RF) of 0.18 eV/V, trapping-time (τ) of 1.0 × 107 s and small subthreshold-swing (SS) of 0.74 V/dec. Relation between thermally activated energy and Hf-ratio clearly indicated Hf acted as carrier suppressors since the increase of Hf-ratio in a-HIZO films. The Hf greatly affected the overall device performance as well as the stability.

Graphical abstractThis letter report findings on the temperature dependence of stability and trapping time properties in amorphous-HfInZnO thin film transistors with different Hf ratio. The optimized 7HIZO TFT that shows large μFE of >11.1 cm2/V s and good stability based in large falling-rate (RF) of 0.18 eV/V, trapping-time (τ) of 1.0 × 107 s and small subthreshold-swing (SS) of 74 mV/dec. Relation between thermally activated energy and Hf ratio clearly indicated Hf acted as carrier suppressors since the increase of Hf ratio in a-HIZO films. The Hf greatly affected the overall device performance as well as the stability.Figure optionsDownload full-size imageDownload as PowerPoint slide