Compound clusters in silicon dioxide obtained by N+, C+ and B+ high-dose ion implantation: Nature of the blue cathodoluminescence emission and relationship with the embedded phases

SiO2 films on Si substrates have been implanted at 600 C by N++C+, N++B+ and N++C++B+ ions at two different doses, and subsequently thermal annealed. Cathodoluminescence measurements of the samples have shown three bands at 3.45, 2.7 and 2.1 eV. The 2.7 eV band, observed in all the samples but more intense in the N+B annealed samples, is due to oxygen deficiency centers, while the 3.45 eV one, only present in N+B and N+C+B samples, seems to be related to BN or B associated centers. Infrared spectra of the implanted films showed Si-O-B and h-BN bands in samples containing B, as well as a contribution about 1200 cm-1 assigned to a ternary compound in the N+C+B implant. No modes different than those of Si-O bond have been found in samples without B. (copyright 2005 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)