| 摘要 |
A semiconductor structure has a density variation in a predetermined direction, and an external stress is applied perpendicular to the predetermined direction. The structure can be a stressed isotope superlattice (10), with density variation parallel to the crystallographic direction of the dominant intervalley scattering (for example, [100] for silicon, and [111] for germanium), and with in-plane stress arising from lattice mismatch with a single crystal overlayer or substrate (11). The external stress may also be applied mechanically, and serves to suppress or enhance phonon scattering in intervalley directions perpendicular to the predetermined direction. Applications include optical devices, transistors, quantum wires and quantum dots. |
