Title :
Mobility simulation in Si/SiGe heterostructure FETs
Author :
Abramo, A. ; Bude, J. ; Venturi, F. ; Pinto, M.R.
Author_Institution :
Dipartimento di Elettronica Inf. e Sistemistica, Bologna Univ., Italy
Abstract :
The behavior of low field effective electron mobility (EEM) in Si/SiGe FETs has been investigated. The results have been obtained solving self-consistently the one dimensional Poisson and Schrodinger equations. Strain induced band splitting has been included in the framework of the model-solid theory (MST). The EEM has been computed in the relaxation-time approximation, including scattering due to optical phonons, elastic acoustic phonons, and surface roughness. The scattering rates have been computed consistently with the 2-D character of the electron gas (2DEG). First-order perturbation theory has been used to account for non parabolic energy dispersion in the scattering rate calculations. The simulator has been applied to study the EEM dependence on gate voltage and device structure. A homogeneous Monte Carlo simulator (HMCS) consistent with the 2-D nature of the electron gas has also been developed and resulting drift velocity and mean energy behavior as a function of the parallel electric field are also presented.<>
Keywords :
Ge-Si alloys; Monte Carlo methods; Schrodinger equation; electron mobility; elemental semiconductors; field effect transistors; semiconductor device models; semiconductor materials; silicon; simulation; surface scattering; surface topography; two-dimensional electron gas; 2DEG; HFET; Schrodinger equation; Si-SiGe; drift velocity; elastic acoustic phonons; first-order perturbation theory; gate voltage; heterostructure FETs; homogeneous Monte Carlo simulator; low field effective electron mobility; mean energy behavior; mobility simulation; model-solid theory; non parabolic energy dispersion; one dimensional Poisson equation; optical phonons; parallel electric field; relaxation-time approximation; scattering rate calculations; strain induced band splitting; surface roughness; two-dimensional electron gas; Acoustic scattering; Computational modeling; Electron mobility; FETs; Germanium silicon alloys; HEMTs; MODFETs; Optical scattering; Phonons; Silicon germanium;
Conference_Titel :
Electron Devices Meeting, 1994. IEDM '94. Technical Digest., International
Conference_Location :
San Francisco, CA, USA
Print_ISBN :
0-7803-2111-1
DOI :
10.1109/IEDM.1994.383285
