1. International Laboratory of Environmental Electron Devices (LAIDEA UNAM), ENES Morelia, National Autonomous University of Mexico, 58190 Morelia, Mexico
2. Semiconductor Optics, Institute of Solid-State Physics, University of Bremen, 28359 Bremen, Germany
3. Research Group of Optical Properties of Materials (GPOM), Centro de Investigaciones en Óptica A.C., A.P. 1-948, 37150 León, Gto., Mexico
4. Laboratory of Microscopy, National School of Higher Studies, ENES Morelia, National Autonomous University of Mexico, 58190 Morelia, Mexico
5. Center for Engineering and Industrial Development, CIDESI, Division of Microtechnologies, 76125 Santiago de Querétaro, Querétaro, Mexico
6. Micro and Nanotechnology Research Center (MICRONA), Veracruz University, Boca del Río, Veracruz 94294, México
7. MAPEX Center of Materials and Processes, University of Bremen, 28359 Bremen, Germany