Title :
High-performance poly-silicon TFTs using HfO2 gate dielectric
Author :
Lin, Chia-Pin ; Tsui, Bing-Yue ; Yang, Ming-Jui ; Huang, Ruei-Hao ; Chien, Chao-Hsin
Author_Institution :
Dept. of Electron. Eng., Nat. Chiao-Tung Univ., Hsinchu, Taiwan
fDate :
5/1/2006 12:00:00 AM
Abstract :
High-performance low-temperature poly-Si thin-film transistors (TFTs) using high-κ (HfO2) gate dielectric is demonstrated for the first time. Because of the high gate capacitance density and thin equivalent-oxide thickness contributed by the high-κ gate dielectric, excellent device performance can be achieved including high driving current, low subthreshold swing, low threshold voltage, and high ON/OFF current ratio. It should be noted that the ON-state current of high-κ gate-dielectric TFTs is almost five times higher than that of SiO2 gate-dielectric TFTs. Moreover, superior threshold-voltage (Vth) rolloff property is also demonstrated. All of these results suggest that high-κ gate dielectric is a good choice for high-performance TFTs.
Keywords :
elemental semiconductors; hafnium compounds; high-k dielectric thin films; thin film transistors; HfO2; Si; high k gate dielectric; thin film transistors; Active matrix liquid crystal displays; Capacitance; Circuits; Dielectric materials; Dielectric substrates; Hafnium oxide; Liquid crystal displays; Low voltage; Thin film transistors; Threshold voltage; Hafnium dioxide; high dielectric-constant dielectric; thin-film transistors (TFTs);
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2006.872832