Atomic Depth Distribution Analysis of In and Ga on Si(111) during Epitaxial Growth and New Surfactant-Mediated Epitaxy

Abstract

Atomic depth distribution and growth modes of In and Ga on a Si(111) surface were studied by a method using reflection high-energy electron diffraction (RHEED) and total reflection angle X-ray spectroscopy (TRAXS). Indium was deposited on a Si(111)-√3×√3-Ga(1 ML) surface at room temperature. After 2 ML and 6 ML of In deposition, the peak positions and the shapes were similar in the glancing angle dependence of GaK emission. By the analysis of these measurements, the growth mode was concluded to be as follows. First, two layers of In grew on the Ga layer in an ordinary growth mode. After the third layer, however, In grew under the third Ga layer, resulting in a layer structure of (In2Ga)Inm (m=1,2,3 ...). On other Ga-covered Si(111) surfaces, In grew in an ordinary growth mode.