Influence of contamination on the dislocation-related deep level C1 line observed in deep-level-transient spectroscopy of n-type silicon: A comparison with the technique of electron-beam-induced current

• Published in: Journal of applied physics 2003-01, Vol.93 (2), p.1069-1074
• Main Authors: Knobloch, Klaus, Kittler, Martin, Seifert, Winfried
• Format: Article
• Language: English
• ISSN: 0021-8979; 1089-7550
• DOI: 10.1063/1.1532938

Misfit dislocations containing different amounts of contamination were analyzed by deep-level-transient spectroscopy (DLTS). The amount of dislocation contamination was determined from the temperature dependence of the dislocation contrast, c(T), measured by electron-beam-induced current (EBIC). The C1 line was not observed for clean 60° dislocations in n-type Si, but appeared upon contamination of dislocations by gold. The density of levels related to C1 measured by DLTS is in good agreement with the density of impurities determined from the EBIC c(T) behavior. The width of the distribution of energy levels that form the C1 line increases with the amount of contamination. It is rather sharp for dislocations contaminated with less than 105 impurities/cm dislocation length, and becomes broadened for dislocations with about 106 impurities/cm length (ΔE=50 meV). The experimental observations are explained by accommodation of impurities in both the core and in the strain field of the dislocations.