In this work we present a study on the carbon incorporation in InGaP layers grown by Chemical Beam Epitaxy as a function of growth temperature. Hall measurements show that the electron concentration increased from 2.3 X 10(14) to 8.9 X 10(16) cm(-3) as the growth temperature increased from 500 degreesC to 560 degreesC. Lower growth temperature InGaP layers are more resistive. Using photoluminescence and a carbon-implanted sample, we identify an acceptor level at nearly 45 meV from the top of the valence band. Part of incorporated carbon acts as an acceptor and part as a donor. The electrical and photoluminescence measurements show that the ratio between acceptors and donors increase as the growth temperature decreases. Due to this compensation, samples grown at lower temperatures (500 degreesC) present a resistively 10(4) times higher than those grown at high temperature (560 degreesC). (C) 2003 Elsevier Science B.V. All rights reserved.