Details

Autor(en) / Beteiligte

• Bukke, Ravindra Naik
• Naik Mude, Narendra
• Lee, Jiseob
• Avis, Christophe
• Jang, Jin

Titel

Effect of Hf Alloy in ZrOx Gate Insulator for Solution Processed a-IZTO Thin Film Transistors

Ist Teil von

• IEEE electron device letters, 2019-01, Vol.40 (1), p.32-35

Ort / Verlag

IEEE

Erscheinungsjahr

2019

Quelle

IEEE Xplore

Beschreibungen/Notizen

• We report the effect of Hf alloy in ZrO x (HZO) gate insulator on the performance and stability of solution-processed amorphous indium-zinc-tin oxide (a-IZTO) thin-film transistors (TFTs). The Hf concentration in ZrO x is varied from 0% to 50 %. The optimized concentration is found to be 10% and the TFT with 10% HfZrO x exhibits the saturation mobility of 4.76 cm<inline-formula> <tex-math notation="LaTeX">^{\textsf {2}}\text{V}^{-\textsf {1}}\,\,\text{s}^{-\textsf {1}} </tex-math></inline-formula>, a subthreshold swing of 70 mV/dec., and <inline-formula> <tex-math notation="LaTeX">{I}_{ \mathrm{\scriptscriptstyle ON}}/{I}_{ \mathrm{\scriptscriptstyle OFF}} </tex-math></inline-formula> current ratio of ~108. The TFT has no hysteresis and a small threshold voltage shift of 0.44 V upon positive-bias-stress at 5 V for 1 h. The improvements are due to the decrease in <inline-formula> <tex-math notation="LaTeX">{V}_{o} </tex-math></inline-formula> (O vacancy) and -OH concentrations and the increase in M-O-M (M: metal) bond concentration at the a-IZTO/HZO interface. This is related with the diffusion of Hf into the a-IZTO active layer by the average concentration of 1.44 at. %.