Cathodoluminescence of epitaxial layers of Insub(1-x)Gasub(x)P(0.7(<=)x<1.0) solid solutions

Epitaxial layers of Insub(1-x)Gasub(x)P(0.7(<=)x<1.0) in the temperature range 300-79 K are investigated. Particular attention has been paid to obtaining sufficiently homogeneous layers of this material. The band system observed in cathodo-luminescence of both undoped and Zn-, Te-doped Insub(1-x)Gasub(x)P is ascribed to the intrinsic exciton recombination (the X+TA, X-TO,X-LA lines), excition recombination involving neutral donors (C-line), hole recombination at neutral donors (D-line), and donor-acceptor recombination (D-A line). The points of transition from direct band structure of Insub(1-x)Gasub(x)P to indirect one are shown to be xsub(c)=0.72+-0.01 (Esub(g)=2.294+-0.003 eV) and 0.73+-0.01 (Esub(g)=2.227+-0.003 eV), respectively