ELECTRON-TRANSPORT THROUGH ANTIDOT SUPERLATTICES IN SI SI0.7GE0.3 HETEROSTRUCTURES/

Transport properties of electrons in antidot superlattices are studied in Si/Ge heterostructures. Lateral superlattices with periods between 830 and 500 nm were imposed upon high-mobility two-dimensional electr on gases in Si/Si0.7Ge0.3 heterostructures by means of laser holograph y and reactive ion etching. Typical features known from GaAs/AlxGa1-xA s samples, such as low-field commensurability oscillations in the long itudinal resistivity rho(xx), additional nonquantized Hall plateaus, a nd quenching of the Hall effect around B = 0, are observed. From the p osition of the commensurability maxima in rho(xx) we conclude that the lateral potential is rather smooth.