Magnetron sputter epitaxy of Si/Ge heterostructures

Radio-frequency magnetron sputter epitaxy was employed for the synthesis of SimGen/Si(001) strained-layer superlattices and of modulation doped, strained Si quantum wells on relaxed Si0.7Ge0.3. Raman spectroscopy was used to demonstrate that the Ge layers of a Si30Ge6/Si(001) superlattice are fully strained and that surprisingly sharp Si/Ge interfaces of similar to 2-4 ML extension result from the sputter epitaxy. Magnetotransport measurements on Si quantum well structures at T = 1.6 K proved the presence of a two-dimensional electron gas with a mobility of 15 800 cm(2) V-1 s(-1) and allowed the observation of the integer quantum Hall effect.