An embodiment is a method. A first III-V compound semiconductor is epitaxially grown in a trench on a substrate, and the epitaxial growth is performed in a chamber. The first III-V compound semiconductor has a first surface comprising a facet. After the epitaxial growth, the first surface of the first III-V compound semiconductor is etched to form an altered surface of the first III-V compound semiconductor. Etching the first surface is performed in the chamber in situ. A second III-V compound semiconductor is epitaxially grown on the altered surface of the first III-V compound semiconductor. The epitaxial growth of the first III-V compound semiconductor may be performed in a MOCVD chamber, and the etch may use an HCl gas. Structures resulting from methods are also disclosed.