Method of forming a field effect transistor and methods of forming integrated circuitry

摘要

A method of forming integrated circuitry includes forming a field effect transistor gate over a substrate. The gate comprises polysilicon conductively doped with a conductivity enhancing impurity of a first type and a conductive diffusion barrier layer to diffusion of first or second type conductivity enhancing impurity received thereover. An insulative layer is formed over the gate. An opening is formed into the insulative layer to a conductive portion of the gate. Semiconductive material conductively doped with a conductivity enhancing impurity of a second type is formed within the opening in electrical connection with the conductive portion, with the conductive diffusion barrier layer of the gate being received between the semiconductive material of the gate and the semiconductive material within the opening. Other aspects are disclosed and claimed.