Photoluminescence characterization of defects created in electron-irradiated silicon at elevated temperatures

Photoluminescence (PL) spectroscopy is employed to investigate radiative de fects created in Si during electron-irradiation at elevated temperatures. T he use of high temperature during electron irradiation has been found to af fect considerably the defect formation process. The effect critically depen ds on the temperature of the irradiation as well as doping of the samples. For carbon-lean Si wafers high temperature electron irradiation stimulates the formation of extended defects, such as dislocations and precipitates. F or carbon-rich Si wafers the increase of irradiation temperature up to 300 degrees C enhances the formation of the known carbon-related defects. In ad dition, several new excitonic PL lines were observed after electron irradia tion at T greater than or equal to 450 degrees C. The dominant new PL cente r gives rise to a BE PL emission at 0.961 eV. The electronic structure of t he 0.961 eV defect is discussed based on temperature-dependent and magneto- optical studies. (C) 2000 Elsevier Science S.A. All rights reserved.