Semi-Analytic Boltzmann Model for the Substrate Current of Short-Channel MOSFETs with Lightly Doped Drains
H.C. Morris, M.M. De Pass
San Jose State University, US
Keywords: boltzmann equation, lightly doped drain, impact ionization, substrate current
As MOSFET sizes have been reduced to nano-scale dimensions, existing models of device
behavior, such as the drift diffusion equations, cease to be valid. In the nano domain, more
fundamental equations, such as the Boltzmann equation and its quantum analogs, must be
utilized. This paper presents a new technique for obtaining practical formulae for the impact
ionization (I.I.) generation rate Gii in ultra-short-channel Lightly Doped Drain (LDD) MOSFETs.
We present relevant new formulae for the substrate current Isub that can be compared with
empirical data and utilized in SPICE-type simulations.
NSTI Nanotech 2003 Conference Technical Program Abstract