AVS 54th International Symposium | |
Surface Science | Thursday Sessions |
Session SS-ThP |
Session: | Surface Science Poster Session |
Presenter: | G. Duvjir, Chonbuk National University, Korea |
Authors: | G. Duvjir, Chonbuk National University, Korea H. Kim, Chonbuk National University, Korea J.M. Seo, Chonbuk National University, Korea |
Correspondent: | Click to Email |
From the previous STM studies of Si(114)-2x1, it had been reported that its pure and reconstructed surface (A-phase) is composed of rebonded restatom(R), tetramer(T), and dimer(D) rows. Recently, during annealing Si(114) near 1300C, we have found carbon-induced Si(114)-2x1 surface (B-phase) whose reconstruction is composed of T, T and D rows. Such a B-phase turns out to be induced by bulk carbon impurity segregated to surface and trapped at the subsurface. Once the surface changes from A-phase to B-phase, it does not return to A-phase by any kind of annealing process. The portion of B-phase relative to A-phase can also be increased by C2H2 adsorption on the clean substrate held at 500 C up to 100 percent. When the surface of B-phase is used as a substrate during Si-homoepitaxy or Ge-epitaxy, the overlayer thickness increases by two layers, differently from one-layer growth mode on the substrate of A-phase. It can be concluded that carbon having a stable subsurface site induces the anisotropic compressive stress on the surface, which results in insertion of Si-dimer to R row to form T row. The potential of this B-phase for application as a template is in its thermal stability and homogeneity since A-phase always has B-phase impurity even in the clean surface.