Ab initio study of the adsorption and desorption of Se on the Si(001) surface


Cakmak M., Srivastava G., Ellialtioglu S., Colakoglu K.

SURFACE SCIENCE, cilt.507, ss.29-33, 2002 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 507
  • Basım Tarihi: 2002
  • Doi Numarası: 10.1016/s0039-6028(02)01170-6
  • Dergi Adı: SURFACE SCIENCE
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.29-33
  • Orta Doğu Teknik Üniversitesi Adresli: Evet

Özet

The adsorption and desorption of Se on the Si(0 0 1) surface are investigated, based upon the ab initio pseudopotential calculations. Following a recent experimental work, three different adsorption models have been studied: 1/2 NIL of Se on the Si-Si dimer with a bridge position within the (1 x 2) surface reconstruction, 1 ML of Se sitting above the topmost Si atoms in bridge absorption site within the (1 x 1) surface reconstruction, and 2 M L of Se half of which is embedded into the Si bulk near the surface within the (1 x 1) surface reconstruct ion. For 1/2 ML, we have found that the vertical displacement between the Se atom and Si-Si dimer is 1.97 Angstrom, close to the experimentally measured value of 2.10 Angstrom. For I ML, the vertical displacement between the Se atom and the Si atoms is 1.41 Angstrom, somewhat smaller than the experimentally measured value of 1.60 Angstrom, For 2 ML, upon relaxation, the embedded Se atoms have diffused upwards. Our results are analysed to provide support to a recent experimental study of desorption of Se from the surface. (C) 2002 Elsevier Science B.V. All rights reserved.