Photoluminescence and structural studies on extended defect evolution during high-temperature processing of ion-implanted epitaxial silicon

Low-temperature photoluminescence (PL) spectroscopy, in conjunction with tr ansmission electron microscopy (TEM) and optical microscopy (OM) have been carried out to investigate the origin of radiative recombination from vario us extended defects that evolve during high-temperature processing of ion-i mplanted epitaxial silicon. From PL studies on N-2-annealed samples, we pro vide spectroscopic evidence of precipitation of the implanted impurities we ll below the solid-solubility limit. This result is being supported by obse rvations from secondary ion mass spectrometry and spreading resistance prof iling of the implanted ions. Cross sectional TEM analyses on these samples reveal < 111 > -oriented precipitates located in a region containing a high dislocation density. Postimplantation annealing in oxygen ambient results in the formation of dislocations and oxidation-induced stacking faults (OIS F). A systematic analysis of PL spectra on different-implanted and preannea led samples, in conjunction with TEM and OM analyses, reveals that the conv entionally observed dislocation-related D1 and D2 lines in the PL spectrum is not a characteristic of the OISF, but of the dislocations only. It is sh own that the OISF acts as a nonradiative channel for luminescence in silico n. Various other sources of nonradiative channels in silicon are also prese nted and the efficacy of photoluminescence technique in the characterizatio n of process-induced defects in silicon is discussed. (C) 2001 American Ins titute of Physics.