Modella
Lateral PNP Bipolar Model
Dedicated Lateral PNP Model
The MODEL-LAteral model developed by Philips N.V. provides an accurate model dedicated to lateral PNP devices.
This model is based on a totally new approach, accounting for the complex
bi-dimensional structure of lateral transistors. Modella allows the simulation
of lateral devices using real physically based parameters, instead of using
less accurate empirically-modified models, such as Gummel-Poon.
With Modella, lateral PNP bipolars do not lack an accurate model anymore.

Influence of excess-phase on current gain

Ic vs. Vce characteristic
Major Improvements
Modella benefits from the following improvements with regard to the older Gummel-Poon model:
- More complex resistive network, using more internal nodes
- Separation of bottom and sidewall components, describing the 2D structure of the transistor
- No nonphysical parameter (for example, current crowding is modeled, using only one parameter)
- Symmetry of the equivalent circuit, thanks to a split base resistance
- Equations derived from PNP formulations
- No iterative process used in equations, resulting in short simulation times
Physically-Based Lateral Bipolar Model
Modella accounts for the bi-dimensional structure of lateral PNP devices, modeling physical effects such as:
- Explicit modeling of inactive regions
- Excess-phase shift for current and storage charges
- Charge storage
- Temperature
- High-injection
- Built-in electric field in base region
- Bias-dependent Early effect
- Low-level non-ideal base currents
- Hard and quasi saturation
- Weak avalanche
- Current crowding and conductivity modulation of thebase resistance
- Hot carrier effects in the collector epilayer
- Split base-collector depletion capacitance
Silvaco Implementation
- Modella is compatible with VZERO and BYPASS options in order to achieve great speed performance
- Internal warnings and diagnostics provide valuable information to help finding convergence issues
- User-friendly parameters checking; user is kept aware of every clipped parameter
- Device internal variables (currents, conductances, charges...) can easily be accessed like any other parameter
- Modella model can be accessed within SmartSpice as level 500
Rev. 012114_04