A solar cell concentrator structure includes a first concentrator element having a first aperture region and a first exit region including a first back surface region and a first corner region. The structure also includes a second concentrator element integrally formed with the first concentrator element. The second concentrator element includes a second aperture region and a second exit region-including a second back surface region and a second corner region. Additionally, the structure includes a first radius of curvature of 0.25 mm and less characterizing the first corner structure and the second corner structure, a first coupling region between the first exit region and a first surface region of a first photovoltaic device. The structure further includes a second radius of curvature of 0.15 mm and less characterizing a region between the first concentrator element and the second concentrator element.