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At present the heteroepitaxial structures based on gallium arsenide and its solid solutions are the basis for manufacturing of solid state electronics devices. The main method of growing heteroepitaxial structures is the chemical deposition from vapors of metalorganic compounds and volatile hydrides. The electrically active impurities, uncontrollably coming into layers during the growing process, worsen the characteristics of the devices based on the heteroepitaxial structures. In this study a comparison of trimethylgallium (TMG) methods of synthesis into the synthesized product from the point of view of incoming of electrically active impurities in gallium arsenide (GaAs) has been carried out. As an object of the study, the methods of TMG obtaining, including the exchange reaction of gallium trichloride with trimethylaluminum (TMA), as well as the organomagnesium syntheses, with metallic magnesium used as an initial reagent, have been chosen. The behavior of the electrically active impurities during the purification of TMG by the rectification method has been studied. The studies have been performed by the methods of spectral analysis and functional control (based on the electrophysical parameters of GaAs epitaxial layers, grown from TMG and arsine. It has been found that the qualitative and quantitative composition of impurities in TMG after the synthesis (crude TMG) depends on their content in the initial reagents. TMG, obtained by the exchange reaction of gallium trichloride with TMA, is a source of the n-type impurities in GaAs. Basically it is an impurity of silicon. TMG, produced using metallic magnesium, is a source of impurities of both p -type (mainly zinc) and n -type (mainly silicon). Regardless of the quality of the crude TMG material, the use of the rectification method at reduced pressure makes it possible to obtain TMG with a low content of impurities. The GaAs epitaxial layers, grown using the purified trimethylgallium samples (TMG rectificate), have the n-type conductivity with a low background doping level ((0.7-4)×10 cm and high mobility of charge carriers - 7300-8500 cm/(V·s) at 300 K and 90 000-15 600 cm/(V·s) at 77 K. This corresponds to the purest samples of GaAs, grown by Metalorganic vapor phase epitaxy (MOVPE) technique using TMG and arsine. Based on the data of the functional control, the content of the impurities, exhibiting the electrical activity in GaAs in the obtained TMG rectificate samples is equal to the level of 10-10.

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