Title :
High-Performance Amorphous InGaZnO Thin-Film Transistors With HfO2/Lu2O3/HfO2 Sandwich Gate Dielectrics
Author :
Jim-Long Her ; Fa-Hsyang Chen ; Wei-Chen Li ; Tung-Ming Pan
Author_Institution :
Div. of Natural Sci., Chang Gung Univ., Taoyuan, Taiwan
Abstract :
In this brief, a high-performance amorphous InGaZnO (α-IGZO) thin-film transistor (TFT) with a HfO2/Lu2O3/HfO2 (HLH) sandwich gate dielectric is demonstrated for the first time. Compared with the Lu2O3 dielectric, the α-IGZO TFT device using an HLH sandwich gate dielectric exhibited a low threshold voltage of 0.43 V, a high field-effect mobility of 17.2 cm2 /Vs, a small subthreshold swing of 104 mV/decade, and a high ION/IOFF current ratio of 3.08 × 10-7, presumably because of the reduction of surface roughness at the dielectric-channel interface. Furthermore, the reliability of voltage stress can be improved using an HLH sandwich dielectric structure.
Keywords :
III-V semiconductors; dielectric materials; gallium compounds; hafnium compounds; indium compounds; lutetium compounds; surface roughness; thin film transistors; zinc compounds; α-IGZO TFT device; HLH sandwich gate dielectric; HfO2-Lu2O3-HfO2; InGaZnO; dielectric-channel interface; high field-effect mobility; high-performance amorphous thin film transistors; subthreshold swing; surface roughness reduction; threshold voltage; voltage 0.43 V; voltage stress reliability; Dielectrics; Hafnium compounds; Logic gates; Rough surfaces; Surface roughness; Thin film transistors; Amorphous InGaZnO ( $alpha $ -IGZO); Amorphous InGaZnO (α-IGZO); HfO₂/Lu₂O₃/HfO₂ (HLH); HfO2/Lu2O3/HfO2 (HLH); Lu₂O₃ gate dielectric; Lu2O3 gate dielectric; thin-film transistor (TFT); thin-film transistor (TFT).;
Journal_Title :
Electron Devices, IEEE Transactions on
DOI :
10.1109/TED.2015.2411738
