Techniques are disclosed for heteroepitaxial growth of a layer of lattice-mismatched semiconductor material on an initial substrate, and transfer of a defect-free portion of that layer to a handle wafer or other suitable substrate for integration. In accordance with some embodiments, transfer may result in the presence of island-like oxide structures on the handle wafer/substrate, each having a defect-free island of the lattice-mismatched semiconductor material embedded within its upper surface. Each defect-free semiconductor island may have one or more crystalline faceted edges and, with its accompanying oxide structure, may provide a planar surface for integration. In some cases, a layer of a second, different semiconductor material may be heteroepitaxially grown over the handle wafer/substrate to fill areas around the transferred islands. In some other cases, the handle wafer/substrate itself may be homoepitaxially grown to fill areas around the transferred islands.