Reverse temperature dependence of Sb sticking on Si(100) surfaces

Abstract

We studied the Sb adsorption phenomenon on clean Si surfaces during molecular beam epitaxy (MBE) as a function of substrate temperature, deposition rate and surface orientation. The concentration of Sb atoms adsorbed on the Si surfaces was measured using X-ray photoelectron spectroscopy (XPS). The adsorption rate increases with the growth temperature. This means that the sticking coefficient increases with the substrate temperature, which is far from the expected behavior. This can be explained by speculating that Sb atoms have insufficient bond energy to break SiSi dimer bonds and form SiSb bonds, and the sticking coefficient increases with the temperature by breaking SiSi bonds assisted by the thermal energy. We also show the substrate orientation dependence of the Sb sticking coefficient and that the difficulty of controlling the doping level can be attributed to the surface sensitivity of the Sb sticking phenomenon.