An analytical model is presented for the 3-D electrostatics of lightly doped GAA square gate MOSFETs operating in the subthreshold domain. The model is based on the assumption of parabolic potential distributions in the directions perpendicular to the gates for the central device regions. The resulting analytical inter-electrode body potential distribution phi(x,y,z) is obtained from the 3D Laplace equation. The model agrees quite well with numerical simulations without any adjustable parameters. Accounting for the electrostatic effects of minority carriers, an expression for the threshold voltage is also derived in terms of lambert functions. In the final manuscript, the model is further explored in terms of subthreshold current and capacitances.
Journal: TechConnect Briefs
Volume: 2, Nanotechnology 2010: Electronics, Devices, Fabrication, MEMS, Fluidics and Computational
Published: June 21, 2010
Pages: 789 - 792
Industry sector: Sensors, MEMS, Electronics
Topics: Compact Modeling