Luminescence analysis of an impurity in the near-surface layer of thermally evaporated silicon

• Published in: Applications of surface science 1982-01, Vol.11, p.375-384
• Main Authors: Aleksandrov, L.N., Lovyagin, R.N., Safronov, L.N.
• Format: Article
• Language: English
• ISSN: 0378-5963
• DOI: 10.1016/0378-5963(82)90085-X

The low-temperature ( T⩽6 K) photoluminescence of surface silicon layers undergoing thermal evaporation in a high vacuum at 1300–1350°C has been studied. It has been found that irrespective of the impurity composition of the initial samples, the bands observed in the luminescence spectra of the surface region of thermally treated plates are due to annihilation of excitons bound with: (1) single non-ionized boron atoms in substitutional positions of the silicon lattice; (2) pairs and clusters of substitutional boron atoms in the layer of about 1 μm thick. The processes resulting in the formation of a narrow Conventration profile of boron atoms near the surface of a silicon plate are discussed. Boron is accumulated due to a considerable difference (by a factor of about 10 2) between the rates of evaporation of boron and silicon atoms under non-steady-state diffusion.