[en] The authors investigated epitaxial heterojunction structures of the following types: In /SUB 1-x1/ Ga /SUB x1/ As/InAs /SUB 1-x/ Px/InAs, In /SUB 1-x/ Ga /SUB x/ As/InAs /SUB 1-y/ P /SUB y/ / InP, and In1-X /SUB 1-x1/ As/... /In /SUB 1-x4/ Ga /SUB x4/ As/InAs, which were obtained by liquid-phase epitaxy with the forced cooling of the molten solution in the 65-700 C range on InAs (111) and InP (111) substrates. The investigations were carried out in a scanning electron microscope equipped with a cathode-luminescence attachment for work in the infrared region of the spectrum at 100 K