Effect of Atomic and Molecular Hydrogen Irradiation on Ge Surface Segregation during Si Molecular Beam Epitaxy

To study hydrogen irradiation effects on Ge surface segregation during Si molecular beam epitaxy, we introduced molecular and atomic hydrogen into a molecular beam epitaxial growth chamber and found that surface segregation is strongly suppressed by atomic hydrogen irradiation, while it is slightly suppressed by molecular hydrogen irradiation. Molecular hydrogen is thought to dissociate into atomic hydrogen at the substrate surface and has the same effect as atomic hydrogen. We believe segregation is suppressed because hydrogen irradiation limits the surface migration of Si and Ge atoms.