Semiconductor device and method for fabricating the same

A method for fabricating a semiconductor device comprising:

• forming an interlayer insulating layer on a substrate on which a first region and a second region are defined, the interlayer insulating layer including a first trench arranged in the first region and a second trench arranged in the second region;
• forming a high-k dielectric layer in the first and second trenches;
• successively forming a diffusion layer and a blocking layer on the high-k dielectric layer in the first and second trenches;
• subsequently performing annealing;
• after performing the annealing, removing the blocking layer in the first and second trenches;
• forming a first barrier layer on the high-k dielectric layer in the first and second trenches;
• forming a first work function adjustment layer in the second trench;
• successively forming a second work function adjustment layer and a second barrier layer in the first and second trenches;
• and
• forming a capping layer that covers the first and second trenches.

A method for fabricating a semiconductor device comprising:

• providing a substrate including a first region and a second region;
• forming a first fin and a second fin that project from the first and second regions, respectively;
• forming first and second dummy gate structures that cross the first and second fins, respectively;
• forming first and second trenches that expose the first and second fins, respectively, through removal of the first and second dummy gate structures;
• forming a high-k dielectric layer that crosses the fins in the first and second trenches;
• successively stacking a diffusion layer and a blocking layer on the high-k dielectric layer and then performing annealing;
• removing the blocking layer;
• forming a first barrier layer in the first and second trenches;
• forming a work function adjustment layer on the first barrier layer in the first and second trenches;
• and
• forming first and second capping layers that cover the first and second trenches, respectively.