A new dopant source of carbon trichloro-bromide (CBrCl3), an inter-substituted compound of two highly efficient dopants viz. CCl4 and CBr4, has been used for the heave carbon doping of GaAs in metal organic vapor phase epitaxy (MOVPE) growth, High doping level of 1.12 x 10(20) cm(-3) was achieved at growth temperature of 600 degreesC and V/III ratio of 10. Self-compensation in the samples was systematically studied using the double Crystal X-ray diffraction. Hall and photoluminescence measurements. Samples with hole concentration Up to 7.36 x 10(19) cm(-3) were free of compensation, while those with higher hole concentrations were found to be compensated. Compensations of the layers were calculated quantitatively from conventional lattice mismatch measurements. Anti-site incorporation of carbon was found to be the dominant compensation mechanism for hole concentration above 7.36 x 10(19) cm(-3). (C) 2002 Elsevier Science B.V. All rights reserved.