SMART-II: a three-dimensional CAD model for submicrometer MOSFET's

The authors describe a three-dimensional CAD model for submicrometer MOSFETs. The model has been implemented in a three-dimensional process/device integrated simulator, SMART-II, using a supercomputer. The MOS device model for hot electron transport is based on a modified current relation including an electron temperature effect in an inhomogeneous field. The need for an improved mobility model in an inversion layer and an impact ionization model using the recent experimental data for the mean free path is discussed with emphasis on the numerical simulation for I/V characteristics of small-geometry MOSFETs from the threshold regime to the avalanche regime. It is found that this approach is effective in realizing a three-dimensional CAD model for 0.5- mu m MOSFETs. An application of the model reveals a three-dimensional effect of avalanche breakdown behavior in small-geometry MOSFETs.>