Some aspects relate to methods of forming an epitaxial layer. In some examples, the methods include ejecting atoms from a molten metal sputtering material onto a heated crystalline substrate and growing a single epitaxial layer on the substrate from the ejected atoms, where the atoms are ejected with sufficient energy that the grown epitaxial layer has at least a partial rhombohedral lattice, and wherein the crystalline substrate is heated to a temperature of about 600 degrees Celsius or less, or about 500 degrees or less. Other aspects relate to materials, such as a material including a single epitaxial layer on top of a crystalline substrate, the layer including one or more semiconductor materials and having at least a partial rhombohedral lattice, or a substantially rhombohedral lattice.