Quenching of luminescence in semiconductors by charged defects

نویسنده

  • M Stoneham
چکیده

Charged point defects and dislocations create internal electric fields that can prevent the binding of carriers to luminescent centres such as N in Gap. This paper calculates the distribution of fields present in a semiconductor and its effect on the lifetime of an electron trapped at a localised impurity The results show a decrease in the fraction of effective luminescent centres with increasing concentration of ionised donors and acceptors Both unscreened dislocations and those with a compensting atmosphere of oppositely charged point defects are considered and the calculations show dark regions around them, as observed

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تاریخ انتشار 2001