Semiconductor devices and methods for fabricating the same

摘要

A semiconductor device includes a substrate including a first region and a second region, a first gate dielectric layer, a first lower gate electrode, and a first upper gate electrode sequentially stacked on the first region, a second gate dielectric layer, a second lower gate electrode, and a second upper gate electrode sequentially stacked on the second region, a first spacer disposed on a sidewall of the first upper gate electrode, a second spacer disposed on a sidewall of the second upper gate electrode, a third spacer covering the first spacer on the sidewall of the first upper gate electrode, and a fourth spacer covering the second spacer on the sidewall of the second upper gate electrode. At least one of a first sidewall of the first lower gate electrode and a second sidewall of the first lower gate electrode is in contact with the third spacer.

主权项

1. A method for fabricating a semiconductor device, comprising:
forming a first gate structure and a second gate structure on a first region and a second region of a substrate, respectively,
wherein each of the first and second gate structures including includes a gate dielectric layer, a metal gate electrode, and a semiconductor gate electrode which are sequentially stacked,wherein the metal gate electrode is in direct contact with the semiconductor gate electrode; and forming a first inner spacer on a sidewall of the first gate structure and a second inner spacer on a sidewall of the second gate structure, wherein the first inner spacer is separated from the metal gate electrode of the first gate structure.