Methods of forming spacers adjacent gate structures of a transistor device

A method of forming a device comprising a sacrificial gate structure with a gate cap positioned above said sacrificial gate structure and a first source/drain region and a second source/drain regions on opposite sides of said sacrificial gate structure, said sacrificial gate structure comprising opposing sidewalls, the method comprising:

• forming a low-k sidewall spacer on and in contact with said opposing sidewalls of said sacrificial gate structure;
• forming a first and a second conformal contact etch stop layer (CESL) above each of said first source/drain region and said second source/drain regions, respectively, said first and second CESLs being positioned on and in contact with said low-k sidewall spacer;
• forming a first insulating material above said first and second CESLs;
• performing a first etching process to recess said first insulating material so as to expose substantially vertically oriented portions of said first and second CESLs and to reduce an initial vertical height of said low-k sidewall spacer and a vertical initial height of said first and second CESLs such that at least a portion of said sidewalls of said sacrificial gate structure are exposed after completion of said first etching process;
• performing a second etching process to remove a portion of a lateral width of said substantially vertically oriented portions of said first and second CESLs so as to form a first and a second trimmed CESL, each of which comprise trimmed substantially vertically oriented portions;
• forming a high-k spacer on opposite sides of said sacrificial gate structure, wherein said high-k spacer is positioned on and in contact with said gate cap, on and in contact with said exposed portions of said sidewalls of said sacrificial gate structure and on and in contact with said trimmed substantially vertically oriented portions of said first and second trimmed CESLs;
• and
• forming a second insulating material above said recessed first insulating material in said first source/drain region and said second source/drain regions and adjacent said high-k sidewall spacer.

A method of forming a device comprising a gate structure with a gate cap positioned above said gate structure and a first source/drain region and a second source/drain region on opposite sides of said gate structure, said gate structure comprising opposing sidewalls, the method comprising:

• forming a low-k sidewall spacer adjacent opposing sidewalls of said gate structure;
• forming a first and a second conformal contact etch stop layer (CESL) above said first source/drain region and said second source/drain region, respectively, said first and second CESLs being positioned adjacent said low-k sidewall spacer;
• forming a first insulating material above said first and second CESLs;
• recessing said first insulating material so as to expose substantially vertically oriented portions of said first and second CESLs;
• removing a portion of a lateral width of said substantially vertically oriented portions of said first and second CESLs so as to form a first and a second trimmed CESL, each of which comprise trimmed substantially vertically oriented portions;
• forming a high-k spacer on opposite sides of said gate structure, wherein at least a portion of said high-k spacer is positioned laterally adjacent said trimmed substantially vertically oriented portions of said first and second trimmed CESLs;
• forming a second insulating material above said recessed first insulating material in said first source/drain region and in said second source/drain region and adjacent said high-k sidewall spacer;
• removing said second insulating material above said recessed first insulating material so as to expose said first and second trimmed CESLs;
• performing an anisotropic etching process so as to remove horizontally oriented portions of said first and second trimmed CESLs and thereby expose underlying regions of epi semiconductor material in said first source/drain region and in said second source/drain region;
• and
• forming a conductive source/drain metallization structure in each of said first source/drain region and said second source/drain region.