Search

The reported circuit simulation model Hiroshima University semiconductor technology academic research center IGFET model silicon-on-insulator (HiSIM-SOI) for the fully depleted SOI-MOSFET is based on a complete surface-potential description. Not only the surface potential in the MOSFET channel, but also the potentials at both surfaces of the buried oxide are solved iteratively, which allows including of all relevant device features of the SOI-MOSFET explicitly and in a physically correct way. In particular, an additional parasitic electric field, induced by the surface-potential distribution at the buried oxide, has to be included for accurate modeling of the short-channel effects. The total iteration time for surface potential calculation with HiSIM-SOI is under most bias conditions only a factor 2.0 (up to a factor 3.0 for some bias conditions) longer than for the bulk-MOSFET HiSIM model, where just the channel surface potential is involved. It is verified that HiSIM-SOI reproduces measured current-voltage (I–V) and 1/ƒ noise characteristics of a 250-nm fully depleted SOI technology in the complete operating range with an average error of 1% and 15%, respectively. Stable convergence of HiSIM-SOI in the circuit simulation is confirmed. [ABSTRACT FROM AUTHOR]

The compact MOSFET model development trend leads to models based on the channel surface potential, allowing higher accuracy and a reduced number of model parameters. Among these, the Hiroshima University Semiconductor Technology Academic Research Center IGFET Model (HiSIM) solves the surface potentials with an efficient physically correct iteration procedure, thus avoiding additional approximations without any computer run-time penalty. It is further demonstrated that excellent model accuracy for higher-order phenomena, which is a prerequisite for accurate RF circuit simulation, is achieved by HiSIM without any new model parameters in addition to those for describing the current-voltage characteristics. [ABSTRACT FROM AUTHOR]

In this paper, a compact model of nonquasi-static (NQS) carrier-transport effects in MOSFETs is reported, which takes into account the carrier-response delay to form the channel. The NQS model, as implemented in the surface-potential-based MOSFET Hiroshima University STARC IGFET model, is verified to predict the correct transient terminal currents and to achieve a stable circuit simulation. Simulation results show that the NQS model can even reduce the circuit simulation time in some cases due to the elimination of unphysical overshoot peaks normally calculated by a QS-model. An average additional computational cost of only 3% is demonstrated for common test circuits. Furthermore, harmonic distortion characteristics are investigated using the developed NQS model. While the distortion characteristics at low drain bias and low switching frequency are determined mainly by carrier mobility, distortion characteristics at high frequency are found to be strongly influenced by channel charging/discharging. [ABSTRACT FROM AUTHOR]