Title :
Distributed charge (sub)micron MOS transistor model
Author :
Charlot, J.-J. ; Toutain, S.
Author_Institution :
Télécom Paris, Ecole Nationale Supérieure des Télécommunications, Paris, France
fDate :
12/1/1986 12:00:00 AM
Abstract :
A new enhancement MOS transistor model applicable in all operating regimes is presented in the paper. Usually, MOS transistor models are based on a global equivalent circuit. The global capacitor value determination must take into account the charge sharing, and charges must be controlled, i.e. Qs + QD + QB + QG = 0 In this model, the distributed charge model (DCM), charges are distributed along the channel and naturally controlled. The threshold voltage notion disappears, perfecting the continuity between `subthreshold¿ and strong inversion. The surface potential profile is determined along the channel in the gradual channel conditions using an expression such as ¿s = ¿s0 + ¿V where ¿ is calculated accurately. The approach used takes into account the 2-dimensional physical behaviour. An analysis of the gate controlled depletion region and the effective channel length determination make possible the use of the model in submicron structures. The new model may have applications in electrical simulation for integrated circuit computer aided design, and in the determination of physical parameters along the MOS transistor channel. No fitting parameter, very often introduced in analytical approaches, is necessary here and the control of charges is obtained.
Keywords :
insulated gate field effect transistors; semiconductor device models; surface potential; 2-dimensional physical behaviour; NMOS transistor; channel length; charge control; distributed charge model; electrical simulation; enhancement MOS transistor model; gate controlled depletion region; gradual channel conditions; integrated circuit computer aided design; submicron structures; surface potential profile;
Journal_Title :
Solid-State and Electron Devices, IEE Proceedings I
DOI :
10.1049/ip-i-1.1986.0044