Homoepitaxial GaAs layers were grown by low-pressure metalorganic vapor phase epitaxy (MOVPE), by using the metalorganic precursors trimethylgallium (TMGa) and the low-toxicity, low-dissociation-temperature tertiary-butyl-arsine (TBAs), in order to exploit the phenomenon of controlled intrinsic carbon doping, Low-temperature photoluminescence. Hall effect and capacitance-voltage measurements were performed on the grown samples. The intrinsic carbon doping was studied as a function of: (i) the growth temperature (ranging between 500degreesC and 640degreesC), (ii) the V/III precursor ratio in the vapour phase (ranging between I and 25) and (iii) the influence of GaAs substrate misorientation (0degrees and 2degrees off toward 110). Although a reduced carbon incorporation rate was expected by using TBAs. which is a benefit in obtaining high purity GaAs. intrinsically p-doped GaAs layers with a hole concentrations up to 6.5 x 10(18) cm(-3) and a cot-responding RT mobility in the range (100-400)cm(2)/Vs were obtained. (C) 2002 Elsevier Science B.V. All rights reserved.