OPTICAL-PROPERTIES OF ZNTE ZN1-XMGXSEYTE1-Y QUANTUM-WELLS AND EPILAYERS GROWN BY MOLECULAR-BEAM EPITAXY/

We have investigated optical properties of ZnTe epilayers, Zn1-xMgxSey Te1-y epilayers, and ZnTe/Zn1-xMgxSeyTe1-y quantum wells (QWs) grown o n (100)-InAs substrates by molecular beam epitaxy. We observed several sharp photoluminescence lines close to the excitonic position and no detectable luminescence from deep levels in ZnTe epilayers. Bright lum inescence has been obtained from Zn1-xMgxSeyTe1-y epilayers which are lattice matched with InAs. The band alignment of ZnTe/Zn1-xMgxTe QWs w as found to be type I. The reduction of the band gap energy of the ZnT e layer due to a tensile strain was confirmed in this structure. Nearl y lattice-matched ZnTe/Zn1-xMgxSeyTe1-y QWs have been fabricated. A ty pe II band alignment was observed for many of these QWs. We estimated bowing parameters not only of the band gap but also of the valence ban d for ZnSeyTe1-y. (C) 1997 American Institute of Physics.