Reconstruction of Excitonic Spectrum During Annealinq of ZnSe:N Grown by Metalorganic Vapor Phase Epitaxy

摘要

The reconstruction of the bound excitonic spectra of MOVPE-grownZnSe:N samples caused by thermal annealing was observed. The resultsof the low temperature photoluminescence, reflection and SIMSmeasurements show that this reconstruction is caused neither by thestrain effect nor by the removal of hydrogen from the samples. Thecalculation of the defect structure and energy by the SCF MO LCAOmethod was carried out, and a new stable configuration of the N..center has been found. A model of reconstruction of the nitrogencenters is proposed, assuming that the transition of N,. centers froma less stable state with distorted T, configuration into theenergetically more favorable distorted C,. configuration occurs dueto thermal annealing, resulting in the correspond- ing changes in theluminescence spectra.