Silicon whose band structure is modified by strain to raise carrier mobility. Tensile strain helps nMOS and compressive strain helps pMOS; it is applied with SiGe source/drain regions, nitride films and the like.
Field: Epitaxial growth
Silicon's lattice constant (0.543 nm) is smaller than SiGe's, so a thin silicon layer grown on relaxed SiGe is stretched in-plane to match, producing tensile strain (strained silicon).
When a thin silicon layer is grown epitaxially on a relaxed…SiGe (silicon-germanium) Effective mass Mobility 4H-SiC Autodoping Critical thickness Epitaxial growth Epitaxial lateral overgrowth (ELO) Heteroepitaxy HVPE (hydride vapor phase epitaxy)