Growth mechanisms of highly mismatched AlSb on a Si substrate.

Authors :: Balakrishnan, G.
Huang, S.
Dawson, L. R.
Xin, Y.-C.
Conlin, P.
Huffaker, D. L.
Source :: Applied Physics Letters; 1/17/2005, Vol. 86 Issue 3, p034105, 3p, 4 Diagrams
Publication Year :: 2005
Abstract: We describe the growth mechanisms of highly mismatched (Δa<subscript>o</subscript>/a<subscript>o</subscript>=13%) defect-free AlSb on Si(001) substrates. Nucleation occurs during the first few monolayers of AlSb deposition by crystalline quantum dot formation. With continued growth, the islands coalesce into a bulk material with no vertically propagating defects. Strain energy from the AlSb/Si interface is dissipated by crystallographic undulations in the zinc-blende lattice, as confirmed by high-resolution transmission electron microscopy (TEM) images. Reciprocal space analysis of the TEM images corroborates a crystallographic rotation associated with the undulations. The resulting AlSb material is >98% relaxed according to x-ray diffraction analysis. [ABSTRACT FROM AUTHOR]