Subthreshold surface potential and drain current models for short-channel pocket-implanted MOSFETs

An analytical subthreshold surface potential model for short-channel pocket-implanted (double-halo) MOSFET is presented. The effect of the depletion layers around the source and drain junctions on channel depletion layer depth, which is very important for short-channel devices, is included. Using this surface potential, a drift-diffusion based analytical subthreshold drain current model for short-channel pocket-implanted MOSFETs is also proposed. A physically-based empirical modification of the channel conduction layer thickness that was originally proposed for relatively long-channel conventional device is made for such short-channel double-halo devices. Very good agreement for both the surface potential and drain current is observed between the model calculation and the prediction made by the 2-D numerical device simulation using Dessis.