Title :
Dual nature of metal gate electrode effects on BTI and dielectric breakdown in TaC/HfSiON MISFETs
Author :
Fukatsu, Shigeto ; Hirano, Izumi ; Tatsumura, Kosuke ; Masada, Akiko ; Fujii, Shosuke ; Mitani, Yuichiro ; Goto, Masakazu ; Inumiya, Seiji ; Nakajima, Kazuaki ; Kawanaka, Shigeru ; Aoyama, Tomonori
Author_Institution :
Adv. LSI Technol. Lab., Toshiba Corp., Yokohama, Japan
Abstract :
We investigated bias temperature instability (BTI) and time dependent dielectric breakdown (TDDB) in TaCx/HfSiON MOSFETs in terms of the effects of TaCx metal gate electrode, using various Ta composition and TaCx thickness. We find a dual nature of TaCx metal gate electrode effects on the reliability. The gate electrode has both positive and negative influence on BTI and TDDB. Though various TaCx layers were deposited on the same HfSiON layer, high composition of Ta in the TaCx layer and thick TaCx layer improve BTI and mobility, while they deteriorate time to breakdown (Tbd) because of the effects of metal gate induced defects.
Keywords :
MOSFET; hafnium compounds; semiconductor device breakdown; semiconductor device reliability; silicon compounds; tantalum compounds; MISFET; MOSFET; TaC-HfSiON; bias temperature instability; metal gate electrode; time dependent dielectric breakdown; Degradation; Dielectric breakdown; Electric breakdown; Electrodes; Large scale integration; MISFETs; MOSFET circuits; Temperature dependence; Threshold voltage; Tin; BTI; TDDB; component; high-k gate dielectrics; metal gate electrode;
Conference_Titel :
Reliability Physics Symposium, 2009 IEEE International
Conference_Location :
Montreal, QC
Print_ISBN :
978-1-4244-2888-5
Electronic_ISBN :
1541-7026
DOI :
10.1109/IRPS.2009.5173280
