Deep-level transient spectroscopy was used to investigate the electronic properties of defects which were introduced into B-doped strained p-type Si1-xGex alloys, where x was equal to 0 or 0.05, during Ar-plasma sputter-etching. These defects were compared with those introduced during electron beam deposition, and after 5.4MeV α-particle irradiation. Four defects, with discrete energy levels ranging from 0.22 to 0.55eV above the valence band, were introduced into p-type material during sputtering. The most prominent defect, as detected in Ar plasma-etched samples, had similar electronic properties to those of defects which were detected after electron and α-particle irradiation. The main defects which were detected in p-type material were also observed in p-type Si0.95Ge0.05. One of the predominant peaks was related to the interstitial-C plus interstitial-O pair. The decrease in activation energy of this defect with increasing Ge content, from x = 0 to x = 0.05 was found to exhibit the same variation as the band-gap of strained SiGe/Si. The energy-level position of the defect relative to the conduction band was therefore the same for x = 0 and x = 0.05; thus indicating that such a level was pinned to the conduction band.

Electronic Properties of Defects Introduced into Strained Epitaxial p-Type SiGe Alloys during Sputter Etching in an Argon Plasma M.Mamor, F.D.Auret, M.Willander, S.A.Goodman, G.Myburg, F.Meyer: Semiconductor Science and Technology, 1999, 14[7], 611-4