This study explores the self-organization of Ge nanostructures on SiGe/Si superlattices grown on Si substrates with the surface normal tilted from (001) towards (111) by up to 25°. Prior studies found two-dimensional ordering of Ge dots on nominally flat Si(001) surfaces with a very homogeneous size distribution. Our results show that the Ge islands are less ordered for tilted Si(001) substrates. For substrates with a miscut of 25°, Ge dots nucleate on top of the ripples that form approximately perpendicular to the [1-10]Si direction, i.e., perpendicular to the step direction. Additionally, we observe the formation of Ge dashes, which align preferentially along the [1-10]Si direction.
ASJC Scopus subject areas
- Physics and Astronomy(all)