| Автор | B T Williams |
| Автор | S J Gurman |
| Автор | S H Baker |
| Автор | E A Davis |
| Дата выпуска | 2000-07-10 |
| dc.description | Structural and optical measurements have been made on a series of amorphous thin films of Si<sub>1-x</sub>Ni<sub>x</sub> with 0<x<0.75, prepared by RF sputtering. We present the results of structural studies using extended x-ray absorption fine structure (EXAFS) and small angle x-ray scattering (SAXS) together with optical measurements of the band gap. The EXAFS analysis gave interatomic distances, partial coordination numbers and Debye-Waller factors for the nearest neighbours of the two atom types. The Ni environment was found to be independent of composition for x<0.5. A small variation in the mean Si-Si distance was also found in this composition range. The SAXS results show phase segregation, on the 30 Å scale, for this composition range. We interpret the structural data in terms of a two-phase model, amorphous Si plus amorphous NiSi, for x<0.5 and a single-phase model for x>0.5. The optical data show that a metal-insulator transition occurs at about 10-15% Ni content. We suggest that this transition should be interpreted in terms of a percolation theory involving regions of conducting amorphous NiSi in an amorphous Si matrix. |
| Формат | application.pdf |
| Издатель | Institute of Physics Publishing |
| Название | Structure and properties of amorphous silicon-metal alloys: I. The Si<sub>1-x</sub>Ni<sub>x</sub> system |
| Тип | paper |
| DOI | 10.1088/0953-8984/12/27/315 |
| Electronic ISSN | 1361-648X |
| Print ISSN | 0953-8984 |
| Журнал | Journal of Physics: Condensed Matter |
| Том | 12 |
| Первая страница | 5971 |
| Последняя страница | 5980 |
| Аффилиация | B T Williams; Department of Physics and Astronomy, University of Leicester, Leicester LE1 7RH, UK |
| Аффилиация | S J Gurman; Department of Physics and Astronomy, University of Leicester, Leicester LE1 7RH, UK |
| Аффилиация | S H Baker; Department of Physics and Astronomy, University of Leicester, Leicester LE1 7RH, UK |
| Аффилиация | E A Davis; Department of Physics and Astronomy, University of Leicester, Leicester LE1 7RH, UK |
| Выпуск | 27 |
