Software Architecture, Algorithm, and Quality Verification for Combo Spice Model Extraction
Publication Date: 2014-Jun-10
The IP.com Prior Art Database
Disclosed is an approach is to build all models of a device family together in an enhanced version of model extraction software. The approach uses an advanced software tool dedicated to the combo Simulation Program with Integrated Circuit Emphasis (SPICE) model extraction.
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Software Architecture , , Extraction
Semiconductor technologies rely on the availability of device families with identical geometry, supply voltage, etc., but different leakage current resulting in different threshold voltages. In the traditional approach of compact model generation, each device of this device family is handed to different model engineers for the extraction of a Simulation Program with Integrated Circuit Emphasis (SPICE) model in parallel. While this approach can be time efficient, the model delivery of multiple individual modelers leads to problems with unwanted crossings between device models, different sensitivity to model parameters and performance levels, etc. Efforts are made toward the control and enhancement of model quality after the model building process is finished. This activity usually starts after the work has been finished by the model engineer and can be very time consuming, if a partial rebuild of the SPICE model becomes necessary.
The core idea of the new approach is to build all models of a device family together in an enhanced version of model extraction software. This means that one single modeler (1 for type N and 1 for type P) is sufficient to finish all models of a device family at the same time. Furthermore, this approach enables quality control of models and highly structured relationships between the SPICE model parameters for the individual family of devices. A graphical user interface (GUI) is put in place to optimize the control of the fitting quality in combo plots. Advanced software architectures are used to enhance user productivity by parallel processing of numerical schemes.
The model extraction follows the procedure listed below using an advanced software tool dedicated to the combo SPICE model extraction:
1. Load data for each device of the family into the software. This can be a set of measured electrical IV data, Technical Computer Assisted Design (TCAD) data, or technology targets.
2. Load a starting model for at least one device of the family into the software. If no model is available for each device, duplicate the available model for all devices of the family.
3. Compare the prediction of the existing starting model with the data set for a first set of initial conditions for all devices together using a graphical interface.
4. Optimize a set of SPICE model parameters to reproduce (or at least partially reproduce) the data set under initial conditions. Numerical methods can be either derivative-based or use stochastic methods. Control especially the relationship between chosen SPICE model parameter values to follow pre-defined trends. It...