Devices & Digital Technology

A gate electrode uses an electric field to control the conductivity of a channel between source and drain. Once the gate voltage is high enough, a conductive channel forms and current can flow; below that threshold, the transistor stays off. The gate is isolated from the channel by a thin oxide layer, so essentially no control current flows.

Learn more in the chapter Field-Effect Transistors →

In a FinFET, the conducting channel stands as a thin, vertical "fin" on the substrate, wrapped by the gate on three sides. This multi-sided wrap gives the gate much better control over the channel than in planar transistors. That reduces leakage currents and allows further shrinking of feature sizes.

Learn more in the chapter Construction of a FinFET →