Nucleation of AlN on the (7x7) Reconstructed Silicon (1 1 1) Surface
E. S. Hellman, D. N. E. Buchanan, C. H. Chen
Bell Laboratories, Lucent Technologies
This article was received on Friday, July 31, 1998 and
accepted on Wednesday, October 21, 1998. Abstract
The
(7x7) reconstructed (1 1 1) surface of silicon is found to be
an excellent surface for the nucleation of epitaxial aluminum nitride, despite
the +23.4% misfit in the AlN/Si system. AlN nucleated above the (7x7) to
(1x1) transition temperature (830°C) is found to contain
30° misoriented grains, while films nucleated below the transition
temperature are single orientation. Optimized aluminum nitride films grown on
(7x7) silicon surfaces make excellent substrates for GaN
heteroepitaxy.