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Si/SiGe Modulation Doped Structures by Gas Source Molecular Beam Epitaxy using Arsenic as a Donor

We have grown Si/SiGe modulation doped quantum wells by gas source molecular beam epitaxy using, for the first time, arsenic as an n-type dopant. The layers are characterised by magnetotransport measurements and SIMS analysis. The latter shows an arsenic concentration in excess of 1019 cm-3 along with strong surface segregation.