Strain-Driven Formation of Nanostripes on In/Si(113) Surface

Periodic nanostripe arrays are observed on In/Si(113) surface using scanning tunneling microscopy. The stripe superstructures are identified as N×1 reconstructions elongating in 2 1 1 or 1 21 direction and consisting of one vacancy line, one Si adatom row, and N-2 In rows, in which N=5 is predominant. The vacancy line formation relieves the strain induced by the Si adatom row and In rows, and plays an important role in stabilizing the stripe structures. The stability of nanostripe structures is demonstrated by analyzing the strain-mediated interaction of vacancy lines in the framework of the Frenkel-Kontorova model, which indicates that the predominant vacancy line period of N=5 corresponds to the minimum Frenkel-Kontorova energy.