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Journal of Physical Studies 21(1/2), Article 1601 [8 pages] (2017)
DOI: https://doi.org/10.30970/jps.21.1601 RESTRUCTURING OF THE DEFECTED STRUCTURE AND CENTERS OF DISLOCATION LUMINESCENCE IN THE p-Si SURFACE LAYERSB. V. Pavlyk, M. O. Kushlyk, D. P. Slobodzyan, R. M. Lys
Ivan Franko National University of Lviv, Faculty of Electronics and Computer Technologies, |
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The changes of the defected structure of the surface layer of $p$-type conductivity silicon crystals under the influence of plastic deformation and high temperature annealing in the flow oxygen atmosphere has been investigated by the methods of capacitive-modulation spectroscopy of deep levels, IR vibrational levels spectroscopy of molecules and atoms, mathematical and computer analysis of real and ideal capacity-voltage characteristics. There is established a special role of dislocations in the surface layer of silicon during the formation of its energy spectrum and rebuilding of the defective structure. Using the method of infrared spectroscopy it is shown the presence of groups of peaks (the values ranging 1050-1200, 1250-1720, 2130-2150, 2370-2400, 2840-3300, 3650-3800 cm$^{-1}$) corresponding to the hydrogen-, oxygen-, carbon-containing complexes and their connections with the atoms of silicon. Plastic deformation and high-temperature annealing of samples lead to changes in the concentration of these complexes. These changes are associated with the increasing of diffusion, adsorption, desorption and generation of dislocations processes efficiency. It is shown that under the concentration of dislocations $\ge105$\,cm$^{-2}$ the surface layer is enriched with the electrically active complexes (dislocation-oxygen, dislocation-vacancy, dislocation-interstitial atoms of silicon), with effective radiative recombination centers. Infrared and capacitive-modulation studies of silicon semiconductor structures impurity composition showed the presence of the O-Si-O complex and as a result of the plastic deformation and high-temperature annealing of their concentration tend to increase. This type of defect affects the absorption and scattering of infrared radiation by reducing the intensity of dislocation-related luminescence of silicon crystals. It is shown the correlation between capacitive-modulation spectra and those of surface states, which allow us to use the second method for express analysis of the defective condition of such semiconductor structures.
PACS number(s): 61.72.Hh, 61.72.Lk, 61.72.uf, 73.20.Hb, 73.20.At