Title :
A unified model for permanent and recoverable NBTI based on hole trapping and structure relaxation
Author :
Ielmini, Daniele ; Manigrasso, Mariaflavia ; Gattel, Francesco ; Valentini, Grazia
Author_Institution :
Dipt. di Elettron. e Inf., Politec. di Milano-IU.NET, Vinci, Italy
Abstract :
Negative bias temperature instability (NBTI) strongly limits reliability of PMOS devices by degradation of threshold voltage, subthreshold slope and transconductance. The physical understanding of the NBTI mechanism is essential for searching paths of NBTI alleviation and providing realistic predictions for CMOS reliability. This work presents a new NBTI model based on hole trapping/detrapping accompanied by structural relaxation in the host dielectric. Simulations account for a time and T dependence of the drain current degradation during NBTI stress. Dynamic NBTI effects are then explained by alternative hole capture and emission during stress and relaxation stages. The impact of the activation energy dispersion on relaxation times is finally discussed.
Keywords :
CMOS integrated circuits; MOSFET; hole traps; semiconductor device models; semiconductor device reliability; thermal stability; CMOS reliability; MOSFET device; NBTI effects; PMOS device reliability; drain current degradation; hole trapping; host dielectric reliability; permanent negative bias temperature instability; recoverable NBTI model; structural relaxation; subthreshold slope degradation; transconductance; Degradation; Dielectrics; MOS devices; Negative bias temperature instability; Niobium compounds; Semiconductor device modeling; Stress; Threshold voltage; Titanium compounds; Transconductance; CMOS reliability; charge trapping; gate dielectric reliability; negative bias-temperature instability; reliability estimation; reliability modeling;
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.2009.5173220
