AlAs/GaAs 10 period superlattices whose periodic lengths are from 100A to 500A were grown by MOCVD. Their uniformity are guaranteed by double crystal X-ray diffraction experiments in which 2nd order satellite peaks are shown. PL peaks of 100A superlattice and 200A quantum well are detected. The samples were beveled by low angle beveling tools, which show enlarged epi-layer stacks. Finally, RTD's which have 50A GaAs well and 25A or 50A AlAs barriers were fabricated. They show NDR effects at room temperature.
