Radiative recombination centers in silicon irradiated by beryllium ions

Low temperature (4.2-80 K) photoluminescence of silicon irradiated by beryllium ions is studied. A large number of radiative recombination centres which include beryllium atoms in their composition is revealed. Transformation of these centres during isochronous annealing is traced. The simplest complex of Besub(I)+Besub(S) isoelectron trap in one point of the lattice dominateds in 400-600 deg C annealing temperature range. At higher temperatures of heating a part of implanted beryllium diffuses to the surface and another part forms new complexes which give 1.1382 and 1.0528 eV lines. Due to the fact that these lines are not seen in an oxygen-free material one can assume that they are associated with Be+O complexes. A complex linear band is revealed in 0.65-0.90 eV region in 400-600 deg C annealing temperature range. The energy position of more than 30 lines in this band is well described by the theory of couple recombination, one of the components being in lattice points, and the other - in the interstitials of silicon lattice. The detailed comparison of line energies in the band with the theory has permitted to assume the presence of Esub(c)-Esub(d)=0.36 eV donor level in interstitial beryllium atom