Silicon surface reconstructions were directly observed in profile by high-resolution transmission electron microscopy. Low-energy surface facets were formed at edges by in situ annealing of a <110> thin specimen at an ambient pressure of 10-9Torr. As well as <111>, <100> and <110> reconstructed surfaces, extensive areas of flat <113> surface were found. By inspection of high-resolution images from the <113> surface a model involving one dimer per surface (1 x 1) unit cell was proposed, suggesting that low-energy surfaces need not be confined to high-symmetry orientations.

Direct Imaging of a Novel Silicon Surface Reconstruction. J.M.Gibson, M.L.McDonald, F.C.Unterwald: Physical Review Letters, 1985, 55, 1765-7