EN
The first results obtained with the use of Ga_{2}S_{3} and Ga_{2}Se_{3} compounds as sources of donor elements for molecular beam epitaxy of Al_{x}Ga_{1-x}Sb (0 ≤ x ≤ 1) and Al_{x}Ga_{1-x}As (0 ≤ x ≤ 0.4) are reported. In GaAs free electron concentrations obtained when incorporating the donors from these sources can be easily controlled in the range of three orders of magnitude. For Al_{x}Ga_{1-x}Sb it was possible to compensate the high concentration of native acceptors and to obtain n-type of conductivity.