High-resolution electron microscope study of silicon on insulator structure grown by lateral solid phase epitaxy

Structural study of L-SPE grown (100)Si/SiO₂ interface after high temperature annealing in Ar has been carried out using HRTEM. On an atomic scale the roughness at the (100)Si/SiO₂ interface is less than a few lattice planes (0.5 nm). When micro-twins are present in the L-SPE layer, almost all of them nucleate at the Si/Si0₂ interface. This is evidence for the formation of (111) growth planes near the interface during the L-SPE growth. The twin/Si0₂ interface is not parallel to the substrate and forms atomically sharp (111) facets. This fact indicates that the interfacial energy of the (11 l)Si/Si0₂ interface is lower than that of the (100)Si/SiO₂ in solid phase.