Methods for fabricating step gate electrode structures for field-effect transistors

摘要

A method is disclosed for forming at least two semiconductor devices with different gate electrode thicknesses. After forming a gate dielectric region, and determining whether a first or second device formed on the gate dielectric region expects a relatively faster gate dopant diffusion rate, a gate electrode layer is formed on the gate dielectric region wherein the gate electrode layer has a step-structure in which a portion thereof for the first device has a relatively larger thickness than that for the second device if the first device has a relatively faster gate dopant diffusion rate.

主权项

1. A method for forming at least two semiconductor devices comprising:
forming a gate dielectric region; determining that a first device formed on the gate dielectric region has a relatively faster gate dopant diffusion rate than a second device formed on the gate dielectric region; forming a doped gate electrode layer on the gate dielectric region, wherein forming the doped gate electrode layer includes doping the first and second devices with predetermined dopants in first and second device portions, respectively; and forming a step-structure in the doped gate electrode layer in which the first device portion has a relatively larger thickness than the second device portion.