Indium segregation in InGaAs/(Al)GaAs quantum wells (QWs) grown by low-pressure metal organic chemical vapor deposition (MOCVD) was studied. The QW heterostructures were grown at different substrate temperatures (T = 650-800degreesC) with and without growth interruption at specified interfaces. The influence of barrier materials (GaAs or AlGaAs) on indium distribution in QWs was investigated. Surface segregation of indium atoms during MOCVD was systematically studied using grazing sputter angle Auger electron spectroscopy and photolumincscence measurements. The increase of indium concentration in growth direction in single QWs and relative shift of composition in close-spaced double QWs were found. Optimization of the interruption time at specified interfaces. the increase of AlAs mole Fraction in AlGaAs barrier and reduction of growth temperature resulted in the decrease of indium surface segregation. Indium segregation ratio R=0.91-0.94 was determined. (C) 2002 Elsevier Science B.V. All rights reserved.