Intrinsic and oxygen-related deep level defects in In-0.5(AlxGa1-x)(0.5)P grown by metal-organic vapor phase epitaxy

Oxygen-related defects in Al-containing semiconductors can degrade luminesc ence efficiency and reduce free carrier lifetime affecting the performance of light emitting devices. We have used the oxygen-doping source, diethylal uminum ethoxide, (C2H5)(2)AlOC2H5, to intentionally incorporate oxygen-rela ted defects during growth of In-0.5(AlxGa1-x)(0.5)P by metal-organic vapor phase epitaxy (MOVPE). Our investigations have identified several defects w hich are present in nonintentionally oxygen-doped n-type In-0.5(AlxGa1-x)(0 .5)P as well as those due to oxygen. Oxygen introduces defect states near t he middle of the band gap. Deep level transient spectroscopy and photolumin escence data obtained over the range of composition 0 < x < 1, are presente d illustrating the trends in defect structure with alloy composition. (C) 1 998 Published by Elsevier Science B.V. All rights reserved.