Patent ID: 9093467
Filing Date: 2015-07-28
Classification: H01L

Abstract:
1. A method of forming a replacement gate structure above a substrate, comprising: forming a sacrificial gate structure above a surface of said substrate, said sacrificial gate structure comprising a sacrificial gate electrode; forming a sidewall spacer adjacent opposite sides of said sacrificial gate electrode; forming a layer of insulating material adjacent said sidewall spacers; performing at least one first etching process to remove a portion, but not all, of said sacrificial gate electrode so as to thereby define a recessed sacrificial gate electrode having a recessed upper surface; performing at least one second etching process to recess said sidewall spacers so as to define recessed sidewall spacers positioned adjacent said recessed sacrificial gate electrode, wherein said recessed sidewall spacers have a recessed upper surface that is positioned above said surface of said substrate and wherein said recessed upper surface of said recessed sidewall spacers, said recessed upper surface of said recessed sacrificial gate electrode and said layer of insulating material define a gate opening; forming a plurality of sidewall spacers above said recessed upper surface of said sidewall spacers within said gate opening, said plurality of sidewall spacers comprising one low-k spacer comprised of an insulating material having a dielectric constant equal to or less than 3.9 that is positioned laterally between two other spacers of said plurality of sidewall spacers; after forming said plurality of sidewall spacers, removing at least said recessed sacrificial gate electrode so as to define, at least in part, a replacement gate cavity; forming a replacement gate structure within said replacement gate cavity; and forming a gate cap layer within said replacement gate cavity above said replacement gate structure.