Single‐crystal epitaxial layers of have been grown using a steady‐state, liquid phase epitaxial growth technique. In the range of they were grown on InAs substrates from liquid compositions on the pseudobinary phase diagram and also from liquids in the In‐rich corner of the ternary phase diagram at temperatures between 580° and 720 °C. In the range of they were grown on InSb substrates from In‐rich liquids with growth temperatures ranging from 480° to 520°C. The grown crystals are homogeneous in the region more than 4µ from the substrate. The optical absorption edges are sharp, similar to the InAs absorption edge. The 300°K energy band gap as a function of composition may be described by the following expression The electrical properties of the alloys with are similar to those of pure , i.e., when typical mobilities are 30,000 cm2/V‐sec at 300°K and 50,000 cm2/V‐sec at 77°K. For alloys with typical mobilities are 67,000 cm2/V‐sec at 300°K and 50,000 cm2/V‐sec at 77°K. Incorporation of Sn during growth of from the pseudobinary liquid at 720 °C was found to give n‐type doping. Under these conditions the distribution coefficient was determined to be 0.01.