Dependence of photoluminescence from beta-FeSi2 and induced deep levels inSi on the size of beta-FeSi2 balls embedded in Si crystals

We fabricated single-crystalline beta -FeSi2 balls with various sizes embed ded in Si crystals by reactive deposition epitaxy (RDE) and following molec ular beam epitaxy (MBE). The photoluminescence (PL) depended on the size of the beta -FeSi2 ball. We observed clear 1.54 mum PL from the sample with a pproximately 100-nm diameter beta -FeSi2 balls, but not from the sample wit h the balls of approximately 150 nm in diameter or bigger. It was found fro m deep level transient spectroscopy (DLTS) measurements that absence of the 1.54-mum PL emission was attributed to the existence of deep levels in the Si crystals around the beta -FeSi2 balls. (C) 2001 Elsevier Science B.V. A ll rights reserved.