title: Strain-driven mound formation of substrate under epitaxial nanoparticles.
abstract: We observe the growth of crystalline SiC nanoparticles on Si(001) at 900 °C using in situ electron microscopy. Following nucleation and growth of the SiC, there is a massive migration of Si, forming a crystalline Si mound underneath each nanoparticle that lifts it 4-5 nm above the initial growth surface. The volume of the Si mounds is roughly five to seven times the volume of the SiC nanoparticles. We propose that relaxation of strain drives the mound formation. This new mechanism for relieving interfacial strain, which involves a dramatic restructuring of the substrate, is in striking contrast to the familiar scenario in which only the deposited material restructures to relieve strain.
authors.affiliation: Department of Mechanical and Aerospace Engineering and the Andlinger Center for Energy and The Environment and ‡IBM Research Division, T. J. Watson Research Center , Yorktown Heights, New York 10598, United States.
authors.forename: Tanya
authors.initials: T
authors.lastname: Gupta
authors.forename: James B
authors.initials: JB
authors.lastname: Hannon
authors.forename: J
authors.initials: J
authors.lastname: Tersoff
authors.forename: Rudolf M
authors.initials: RM
authors.lastname: Tromp
authors.forename: John A
authors.initials: JA
authors.lastname: Ott
authors.forename: John
authors.initials: J
authors.lastname: Bruley
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Steingart
keywords: AFM; LEEM; Si(100); SiC; TEM; interfacial strain