Title :
Effects of Channel Orientations, High-? Gate Stacks and Stress on UTB-FETs: A QDD Simulation Study
Author :
Silvestri, Luca ; Reggiani, Susanna ; Gnani, Elena ; Gnudi, Antonio ; Rudan, Massimo ; Baccarani, Giorgio
Author_Institution :
ARCES & DEIS, Bologna Univ., Bologna
Abstract :
In this work we propose a unified model for the low-field effective electron mobility in SOI and DG-MOSFETs with ultrathin SiO2/HfO2 gate stacks, different substrate and channel orientations and uniaxial stress conditions.The model accounts for quantum-confinement effects in the MOSFET channel. Next, we apply this mobility model to a 1D quantum drift-diffusion (QDD) transport model in order to investigate the extent to which the low-field mobility impacts the I-V characteristics. Short (Lg = 22 nm) DGFETs,where mobility is affected by quantum-confinement effects, ultrathin SiO2/HfO2 gate stacks and metal gate,have been investigated. Finally, the correlations between the mobility enhancement induced by uniaxial stress in a 22 nm DG-FET, the on-current and transconductance are examined.
Keywords :
MOSFET; electron mobility; hafnium compounds; semiconductor device models; silicon compounds; silicon-on-insulator; 1D quantum drift-diffusion transport model; DG-MOSFET; I-V characteristics; QDD simulation; SOI; Si-SiO2; SiO2-HfO2; UTB-FET; channel orientation; high-kappa gate stacks; low-field effective electron mobility; mobility enhancement; quantum-confinement effects; size 22 nm; uniaxial stress conditions; Capacitance; Circuit testing; Conferences; Differential equations; Electron mobility; Hafnium oxide; Quantization; Scattering; Tensile stress; Voltage; MOSFETs; high-k; low-field mobility; stress;
Conference_Titel :
Design and Test of Nano Devices, Circuits and Systems, 2008 IEEE International Workshop on
Conference_Location :
Cambridge, MA
Print_ISBN :
978-0-7695-3379-7
DOI :
10.1109/NDCS.2008.19
