The surface segregation of phosphorus, antimony, and boron in Si molec
ular-beam epitaxy is investigated experimentally at low temperatures.
Rate and temperature dependent measurements are explained by a segrega
tion model, which connects surface segregation with surface diffusion.
The model is found to explain quantitatively many available data of s
egregation on different semiconductor surfaces, explicitly: Si, Ge, an
d GaAs.