Dependence of SPICE Level 3 model parameters with transistor size

An automated sequential parameter extraction procedure was applied to different MOS device sizes, for the SPICE Level 3 model, to investigate the transistor size influence on the extracted parameters. The extractor was fast enough to be used directly on wafer mapping. The results of its use on different size devices are presented. The parameters extracted on 21 groups of NMOS transistors with varying sizes are presented. The curves show that there are important variations, and an accurate fit can only be achieved if the parameters used are a function of device size.<
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