Carbon atomic chain formation on the beta-SiC(100) surface by controlled sp -> sp(3) transformation

We use atom-resolved scanning tunneling microscopy to evidence the formatio n of carbon atomic chains on the C-terminated beta-SiC(100) surface. These carbon atom lines, which exhibit an extremely high thermal stability (up to approximate to 1200 degrees C), comprise buckled single bond C-C dimers (s p(3)) having a direction perpendicular to the C=C triple bond dimers (sp) f orming a c(2 x 2) surface reconstruction. Their presence does not result in /or from surface antiphase boundaries, and their density increases with ann ealing time. The results suggest anisotropic (tensile and compressive) surf ace stress as a leading driving force in this carbon sp --> sp(3) diamondli ke temperature controlled transformation.