Photo luminescence properties of ZnTe homoepitaxial films deposited by synchrotron-radiation-excited growth

ZnTe homoepitaxial films have been deposited at substrate temperatures betw een 27 degreesC and 100 degreesC by synchrotron-radiation-excited growth us ing diethylzinc and diethyltelluride. Effects of diethylzinc transport rate and substrate temperature upon the photo luminescence properties of the Zn Te films have been clarified. Strong deep level emissions centered at 1.85 and 2.1 eV related to defects such as vacancy-impurity complex become emerg ed with increasing diethylzinc transport rate or substrate temperature. A s harply excitonic emission at 2.375 eV associated with shallow acceptors is observed and neither a donor-acceptor pair recombination nor a deep level l uminescence signal is detected in the spectrum of the film grown under the nearly stoichiometric condition, which indicates that ZnTe films of good qu ality can be grown even at room temperature by this growth technique. (C) 2 001 Elsevier Science B.V. All rights reserved.