Fast monte carlo statistical analysis using threshold voltage modeling

摘要

A system, method, and computer program product for automatically approximating conventional Monte Carlo statistical device model evaluation for circuit simulation with drastic speed improvements, while preserving significant accuracy. Embodiments enable quick inspection of the effects of process mismatch variations on single devices and even large circuits compared to standard computationally prohibitive Monte Carlo analysis. Statistical device model variation is calculated as if all such variation is due to changes in threshold voltage, even though other physical phenomena are known to contribute. Threshold voltage variation is modeled as a function of statistical variation, device size, and working bias condition. Circuit simulation is faster when the full internal device model parameter set is not rebuilt for every Monte Carlo analysis iteration. Embodiments are compatible with both conventional SPICE and newer Fast SPICE simulations. Circuit designers may capture design sensitivity to manufacture process changes more easily with simplified statistical models.

主权项

1. A computer-implemented method comprising:
assigning device behavior variation to a dominant parameter variation; separating the dominant parameter variation into a device geometry dependent term and a process and device type dependent term; and performing a Monte Carlo circuit simulation on a computer, including calculating device behavior variation from the dominant parameter variation for selected values of device geometry and applied voltage.