Methods of forming replacement gate structures on semiconductor devices and the resulting device

A method, comprising:

• forming a sacrificial gate structure and a gate cap layer above said sacrificial gate structure;
• forming first sidewall spacers adjacent opposite sides of said sacrificial gate structure and said gate cap layer;
• forming a layer of insulating material adjacent each of said first sidewall spacers;
• performing at least one etching process to remove said gate cap layer and a portion of said first sidewall spacers so as to expose portions of said layer of insulating material and to define reduced-height first sidewall spacers;
• forming second sidewall spacers on said exposed portions of said layer of insulating material, wherein each of said second sidewall spacers is positioned above one of said reduced-height first sidewall spacers;
• after forming said second sidewall spacers, performing an etching process on said reduced-height first sidewall spacers to form a recess in said reduced-height first sidewall spacers, wherein said recess is self-aligned with respect to said second sidewall spacers;
• after forming recesses in said reduced-height first sidewall spacers, removing said sacrificial gate structure to thereby define a gate cavity, whereby a first portion of said gate cavity is laterally defined by said second sidewall spacers and a second portion of said gate cavity is laterally defined by said recesses;
• and
• forming a replacement gate structure in said gate cavity, wherein at least a first portion of said replacement gate structure is positioned between said second sidewall spacers and a second portion of said replacement gate structure is positioned between said recesses.