Electronic absorption of interstitial boron-related defects in silicon

We report the data on the electronic absorption of interstitial boron-related defects in silicon, irradiated with 5MeV electrons. Two new electronic absorption features have been revealed in the spectrum of boron-doped Si. The sharp line at 4385.2cm(-1) is detected in Si irradiated at 80K and subjected to the subsequent annealing up to 300K. The emergence of the registered line depends on the concentration of boron and does not depend on the presence of oxygen and carbon in the samples. The revealed line is associated with BiBs complex. It is shown that the presence of oxygen in the samples inhibits the formation of BiBs defects. The disappearance of the 4385.2cm(-1) line upon annealing is accompanied by the emergence of a line at 7829.5cm(-1) in the spectrum. The appearance of the 7829.5cm(-1) line depends on the presence of carbon in the samples. The registered 7829.5cm(-1) line is ascribed to BiCs complex. It is argued that, in the oxygen-rich material, B-i liberated as a result of the dissociation of both BiOi and BiBs defects are involved in the formation of BiCs. In oxygen-lean Si, only B-i liberated at the dissociation of BiBs participate in the formation of BiCs. (C) 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim