10
Compact Models for Integrated Circuit Design
solutions are possible by equating the saturation drain current to the model
drain current equation, at V ds = V dsat . The velocity–field relation requires special treatment to be able to include the effect of longitudinal field-dependent
mobility in the integration of the continuity equation. A good approximation
was proposed by Arora et al. [62]. The small geometry effect and different
physical effects including QM and polysilicon depletion effects are implemented in the CAD-oriented analytical MOSFET model [61]. QMEs on the
inversion charge density can be handled in a physical manner by a bandgapwidening approach [65].
The development of f s -based Hiroshima University STARC IGFET Model,
referred to as the HiSIM, has been started in the early 1990s based on the
drift-diffusion concept and proved its feasibility for real applications [66–68].
Since 1993, the model has been successfully applied in the development of
dynamic random-access memory (DRAM), subthreshold region ICs, and
IC-card products at Siemens. In HiSIM, the surface potentials are obtained by
solving the Poisson’s equation iteratively both at the source side and at the
drain side with an accuracy of 10 pV, and simulation speed is comparable to
industry standard V th -based models [66]. The reported accuracy is absolutely
necessary for maintaining sufficient accurate solutions for transcapacitance
values and achieving stable circuit simulation [69]. The salient features of
HiSIM include accurate modeling of small geometry effects, polydepletion
effects, and QM effects in MOSFETs. This is accomplished by modifying
the generalized expression for f s to include a shift in V th due to the abovereferred physical effects. The HiSIM modeling approach automatically preserves scalability of model parameters, and thus, one model parameter set
for all device dimensions is used. Since a complete f s -based model automatically preserves the overall model consistency through f s , the number
of model parameters can be drastically reduced in comparison to the conventional V th -based models [68]. This parameter reduction comes without
any loss in the reproduction accuracy of measurement data (e.g., I–V characteristics). Moreover, it has been reported that the nonlinear phenomena
such as harmonic distortions are accurately calculated automatically [69].
All higher-order phenomena observed such as noise have been shown to
be determined by the potential gradient along the channel [69], which again
highlights the strength of the concept of f s -based modeling. Investigations
of the high-frequency small-signal behavior with HiSIM concluded that the
NQS effect is not as strong as previously believed [70,71]. Three members of
the HiSIM family have been selected as the industry standards by CMC [48].
HiSIM-HV (1st standard version released in January 2009) is the high-voltage
MOS device model standard, HiSIM2 (1st standard version released in
April 2011) is the second-generation MOSFET model standard, and HiSIMSOI (1st standard version released in July 2012) is the surface-potential SOIMOSFET model standard.
At Philips Semiconductors, the development of MOS model 11 or MM11
started in 1994, primarily aimed at simple and accurate digital, analog, and RF
Compact Models for Integrated Circuit Design
solutions are possible by equating the saturation drain current to the model
drain current equation, at V ds = V dsat . The velocity–field relation requires special treatment to be able to include the effect of longitudinal field-dependent
mobility in the integration of the continuity equation. A good approximation
was proposed by Arora et al. [62]. The small geometry effect and different
physical effects including QM and polysilicon depletion effects are implemented in the CAD-oriented analytical MOSFET model [61]. QMEs on the
inversion charge density can be handled in a physical manner by a bandgapwidening approach [65].
The development of f s -based Hiroshima University STARC IGFET Model,
referred to as the HiSIM, has been started in the early 1990s based on the
drift-diffusion concept and proved its feasibility for real applications [66–68].
Since 1993, the model has been successfully applied in the development of
dynamic random-access memory (DRAM), subthreshold region ICs, and
IC-card products at Siemens. In HiSIM, the surface potentials are obtained by
solving the Poisson’s equation iteratively both at the source side and at the
drain side with an accuracy of 10 pV, and simulation speed is comparable to
industry standard V th -based models [66]. The reported accuracy is absolutely
necessary for maintaining sufficient accurate solutions for transcapacitance
values and achieving stable circuit simulation [69]. The salient features of
HiSIM include accurate modeling of small geometry effects, polydepletion
effects, and QM effects in MOSFETs. This is accomplished by modifying
the generalized expression for f s to include a shift in V th due to the abovereferred physical effects. The HiSIM modeling approach automatically preserves scalability of model parameters, and thus, one model parameter set
for all device dimensions is used. Since a complete f s -based model automatically preserves the overall model consistency through f s , the number
of model parameters can be drastically reduced in comparison to the conventional V th -based models [68]. This parameter reduction comes without
any loss in the reproduction accuracy of measurement data (e.g., I–V characteristics). Moreover, it has been reported that the nonlinear phenomena
such as harmonic distortions are accurately calculated automatically [69].
All higher-order phenomena observed such as noise have been shown to
be determined by the potential gradient along the channel [69], which again
highlights the strength of the concept of f s -based modeling. Investigations
of the high-frequency small-signal behavior with HiSIM concluded that the
NQS effect is not as strong as previously believed [70,71]. Three members of
the HiSIM family have been selected as the industry standards by CMC [48].
HiSIM-HV (1st standard version released in January 2009) is the high-voltage
MOS device model standard, HiSIM2 (1st standard version released in
April 2011) is the second-generation MOSFET model standard, and HiSIMSOI (1st standard version released in July 2012) is the surface-potential SOIMOSFET model standard.
At Philips Semiconductors, the development of MOS model 11 or MM11
started in 1994, primarily aimed at simple and accurate digital, analog, and RF