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Threshold Voltage

  • Narain Arora
Part of the Computational Microelectronics book series (COMPUTATIONAL)

Abstract

One of the most important physical parameters of a MOSFET is its threshold voltage V th , defined as the gate voltage at which the device starts to turn on. The accurate modeling of threshold voltage is important to predict correct circuit behavior from a circuit simulator. Since V th has profound effect on circuit operation, it is often used to monitor process variations. Present day MOS process invariably use ion implantation into the channel region, a step often called the threshold adjust implant, that alter the doping profile near the surface of silicon substrate. By changing dose and energy of the threshold implant a desired threshold voltage is achieved. The threshold voltage is by no means a constant quantity but varies with the back bias. With larger back bias, circuits have slower transitions due to decreased drain current and as a result, noise margins decrease.

Keywords

Threshold Voltage Gate Voltage Channel Length Short Channel Strong Inversion 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag/Wien 1993

Authors and Affiliations

  • Narain Arora
    • 1
  1. 1.Digital Equipment CorporationHudsonUSA

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