Photoluminescence, deep level transient spectroscopy and transmission electron microscopy measurements on MeV self-ion implanted and annealed n-type silicon

Deep-level transient spectroscopy (DLTS), photoluminescence (PL), and trans mission electron microscopy (TEM) measurements have been made on n-type sil icon after implanting with 5.6 MeV Si3+ ions using doses of 10(9)-10(14) cm (-2) and anneals at 525 and 750 degrees C. In all the samples, there is onl y a small dependence of the widths and energies of the PL zero-phonon lines on implantation dose, allowing the high resolution of PL to be exploited. In samples annealed at 525 degrees C, the PL intensity can provide a measur e of the concentration of defects over the implantation range, 10(9)-10(12) cm(-2). Carbon-hydrogen complexes are identified as transient species with increasing dose, and the "T" center is related to a DLTS trap 0.20 eV belo w the conduction band energy E-c. At the highest doses in these samples, TE M imaging shows the presence of nanometer-sized clusters, and the PL spectr a show that many previously unreported defects exist in the implanted zone, in addition to two broad bands centered on similar to 885 and similar to 9 30 MeV. The multiplicity of defects supports recent suggestions that a rang e of interstitial complexes is present in the annealed samples. Annealing a t 750 degrees C produces complete recovery in both the DLTS and PL spectra for doses of less than 10(13) cm(-2). At higher doses, {113} self-interstit ial aggregates are observed in TEM, along with the "903" PL signal associat ed with the {113} defects, and the E-c-0.33 eV "KA" DLTS trap. These data s upport the recent identification of that trap with the {113} defects. The w ell-resolved PL spectra show that many previously reported defects also exi st in samples implanted with a dose of 10(14) cm(-2) and annealed at 750 de grees C, again implying the presence of a range of interstitial complexes. (C) 2000 American Institute of Physics. [S0021-8979(00)00218-8].