Tatjana V. Pesic

3D simulation of cross-shaped Hall sensor and its equivalent circuit model

The complete technology process flow and electrical characteristics of cross-shaped Hall sensor in high voltage bulk CMOS technology have been accurately simulated in 2D and 3D using ISE TCAD system. Consistent 3D doping profile is obtained by interpolation, exchanging data between several 2D doping profiles. In order to facilitate the analysis of an electrical circuit incorporating a Hall sensor, an appropriate equivalent circuit model of cross-shaped Hall sensor with voltage control non-linear resistors is suggested. Finally, the results acquired by 3D electrical characteristic simulations using ISE tool DESSIS and equivalent-circuit analyses using program SPICE are compared.

An analytical model of the inverse base width modulation effect in SiGe graded heterojunction bipolar transistors

Abstract The analytical model of the collector current ideality factor degradation at high V be in modern SiGe graded base heterojunction bipolar transistors (HBTs) has been developed for the first time. It is subsequently used for the analysis of the inverse base width modulation (IBWM) effects in SiGe HBTs with respect to collector current degradation, current gain premature roll-off and SiGe base transit time. Comparing the IBWM effects calculated for HBTs with various base impurity concentration doping profiles and the Ge grading, we have found that the careful optimization of SiGe base parameters may substantially minimize negative influence of the IBMW effects on the HBT electrical parameters.

A compact nonquasi-static MOSFET model based on the equivalent nonlinear transmission line

A compact physics-based nonquasi-static (NQS) metal-oxide-semiconductor field-effect transistor (MOSFET) model with the equivalent nonlinear transmission line (TL) representing channel carriers drift-diffusion transport is developed and implemented in the simulation program with integrated circuit emphasis (SPICE) program. An auxiliary subcircuit is described, which efficiently solves the channel surface boundary potentials without the need for employing separate iterative algorithms. The short-channel effects and the quantum effects are efficiently included owning to a surface-potential-based modeling approach. In comparison with other Berkeley short-channel IGFET model 3 (BSIM3)-based NQS MOSFET models, it is shown that the new NQS TL model has the advantages in higher accuracy and substantially fewer number of model parameters. From comparison with a two-dimensional device simulator, it is demonstrated that the new NQS TL model can accurately predict dc, ac, and transient behavior of long- and short-channel n-type MOSFETs in all operational regions and for the input signal frequencies up to 10 f/sub T/ values, using only one set of model parameters.

Dynamic MAGFET model for sensor simulations

A new model for a magnetic-sensitive split-drain MOSFET (MAGFET) consisting of only two n-channel MOS transistors (NMOSTs) in the equivalent sub-circuit is described. The model developed is based on the non-quasi-static MOST model of a conventional NMOST, modified to include the effects of the Lorentz force. On the basis of the results of three-dimensional numerical device simulations, it is shown that the new model can accurately predict the absolute and the relative MAGFET sensitivity for a wide range of the device biasing conditions. Unlike previous models, the new MAGFET model can also predict device dynamic response to time-varying magnetic fields more realistically.

Physical-based non-quasi static MOSFET model for DC, AC and transient circuit analysis

In this paper, we describe a compact physical-based non-quasi static (NQS) MOST model for SPICE. Based on the comparison with results of 2-D device simulations, it is shown that new NQS model can accurately predict NMOST behavior during DC, AC and transient operation.

1D physically based non-quasi-static analog behavioral BJT model for SPICE

A compact 1D non-quasi-static BJT model (NQS BJT) based on the analog behavioral modeling capabilities of the SPICE simulator is described. The NQS BJT model parameters are derived directly from the physical device structure. A momentum relaxation time parameter is also included as equivalent inductivity, yielding more accurate prediction of unity gain frequency and phase characteristics. The efficiency of the novel NQS model is demonstrated by comparison with the standard Gummel-Poon model and experimental results.

Transmission line model of arbitrarily doped base including all injection levels and Kirk effect

It is shown that minority-carrier transport through quasi-neutral base region at all injection levels can be successfully modelled by nonlinear inhomogeneous lossy transmission line. The efficient iterative method of solving I/U distribution along such complex transmission line is presented, as well as novel approach to include Kirk effect.

Transient analysis of BJT using all injection level TLEC model

Transmission line equivalent circuit model of bipolar junction transistor has been generalized to include all injection level case and model Kirk effect. The obtained model has been used for simulation of time domain transient analysis.