US Patent 8629426 Source/drain stressor having enhanced carrier mobility manufacturing same

Various source/drain stressors that can enhance carrier mobility, and methods for manufacturing the same, are disclosed. An exemplary source/drain stressor includes a seed layer of a first material disposed over a substrate of a second material, the first material being different than the second material; a relaxed epitaxial layer disposed over the seed layer; and an epitaxial layer disposed over the relaxed epitaxial layer.