Correlation of charge trapping and electroluminescence in highly efficient Si-based light emitters

In this paper we report on recent results on charge trapping and electroluminescence (EL) from Ge rich SiO2 layers. Thermally grown View the MathML source thick SiO2 layers were implanted with Ge ions at energies of 30–View the MathML source to peak concentrations of 1–View the MathML source%. Subsequently rapid thermal annealing was performed at 1000°C for 6, 30 and View the MathML source under a nitrogen atmosphere in order to form luminescence centers. A combination of capacitance–voltage (CV) and current–voltage (IV) methods was used for the investigation of the trapping properties. It was found that at electric fields View the MathML source electron trapping dominates while at higher electric fields which are typically required for the EL operation of the devices positive charge trapping occurs. It is assumed, that the trapping sites which are responsible for the trapping of the positive charge are in strong relation to the defects causing the luminescence.