Photoluminescence spectroscopy of an Al-C complex in silicon

Were we describe the results of an investigation of an Al-C defect complex in silicon. The defect center, with a zero-phonon line energy at similar to 922 meV, is produced by anneals at temperatures in the region 450-550 degr ees C for times ranging from 8 h to hundreds of hours. Uniaxial stress meas urements have shown that thr: defect symmetry is monoclinic I (point group C-1h), and Zeeman spectroscopy reveals that the transition can be regarded as the recombination of a spinlike electron and hole, with a slight anisotr opy evident in the hole g factor due to mixing of orbital character into th e hole wave function. Our investigations have led us to agree with previous suggestions that the defect is an Al-C complex. Perhaps most interestingly , we see striking parallels between this defect and a previously reported A l pair defect, displaying almost identical uniaxial stress and Zeeman behav ior, with a zero-phonon line energy difference of similar to 37 meV. The re lationship between these two defects is discussed in terms of similar behav ior shown by other defects in silicon. [S0163-1829(99)00915-7].