SULFUR POLYTROPISM IN GALLIUM PHOSPHIDE
Cz-grown GaP(S) signle crystals have been studied. We show that the sulfur content in GaP(S) in the form of a shallow donor at a concentration of <1 10<sup>19</sup> cm<sup>-3</sup> is 0.12 of the total sulfur content in the crystal. Also, we found that the sulfur polytropism in these crystals is accounted for by sulfur dissolution in the form of Ga<sub>2</sub>S<sub>3 </sub>molecules forming a Ga<sub>3-<i>x</i></sub><i></i>P<sub>1-<i>x</i></sub><i></i>S<sub>3<i>x</i></sub><i></i> pseudobinary solid solution. This is nature of sulfur polytropism. The study also showed that microdefect formation is caused by the precipitation of an intrinsic component, i.e gallium.