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The ZnSe epilayers were grown on the GaAs substrate by hot wall epitaxy. After the ZnSe epilayers treated in the vacuum-, Zn-, and Se-atmosphere, respectively, the defects of the epilayer were investigated by means of the low-temperature photoluminescence measurement. The dominant peaks at 2.7988 eV and 2.7937 eV obtained from the PL spectrum of the as-grown ZnSe epilayer were found to be consistent with the upper and the lower polariton peak of the exciton, I 2 (D°, X), bounded to the neutral donor associated with the Se-vacancy. This donor-impurity binding energy was calculated to be 25.3 meV. The exciton peak, I/, at 2.7812 eV was confirmed to be bound to the neutral acceptor corresponded with the Zn-vacancy. The 1^ peak was dominantly observed in the ZnSe/GaAs:Se epilayer treated in the Se-atmosphere. This Se-atmosphere treatment may convert the ZnSe/GaAs:Se epilayer into the p-type. The S A peak was found to be related to a complex donor like a (V Se-VJ-VÎ NTRODUCTION ZnSe has been recently tried to grow the p-type ZnSe for fabricating blue laser diode and light emitting diode [1-8]. Generally, the grown ZnSe epilayer is known to be n-type. Therefore, a major problem for obtaining better device performance is to grow the p-type ZnSe layer with low electrical resistivity. The difficulty in the p-type growth and the conductivity control for ZnSe are well known to be strongly related to the native defects and self-compensation of the ZnSe due to the stoichiometric deviation generated during the growth or the additional thermal treatment [9,10]. The stoichiometric deviation is mainly

The p-CdIn 2 Te 4 single crystal was grown in the three-stage vertical electric furnace by using Bridgman method. The quality of the grown crystal has been investigated by the x-ray diffraction and the photoluminescence measurements. From the photoluminescence spectra of the as-grown CdIn 2 Te 4 crystal and the various heat-treated crystals, the (D o , X) emission was found to be the dominant intensity in the photoluminescence spectrum of the CdIn 2 Te 4 :Cd, while the (A o , X) emission completely disappeared in the CdIn 2 Te 4 :Cd. However, the (A o , X) emission in the photoluminescence spectrum of the CdIn 2 Te 4 :Te was the dominant intensity like an as-grown CdIn 2 Te 4 crystal. These results indicated that the (D o , X) is associated with V Te acted as donor and that the (A o , X) emission is related to V Cd acted as acceptor, respectively. The p-CdIn 2 Te 4 crystal was found to be obviously converted into the n-type after annealing in the Cd atmosphere. The origin of (D o , A o ) emission and its TO phonon replicas is related to the interaction between donors such as V Te or Cd int , and acceptors such as V Cd or Te int . Also, the In in the CdIn 2 Te 4 was confirmed not to form the native defects because it existed in the stable form of bonds.