Surface bismuth removal after Bi nanoline encapsulation in silicon

It is shown by RHEED observation that the thermal desorption is not suitable for this purpose, because the one-dimensional structure of the buried Bi line is disrupted over the same time scale as for removal of the surfactant Bi. Chemical wet etching of the surface layer was found to be a better solution to the removal of the surfactant Bi atoms without destroying the buried Bi lines.