One of the most important problems in our society is the lack of clean energy sources to overcome the energetic crisis and global warming. For this reason, I enrolled “Master en Energías Renovables y Eficiencia Energética” at UNI. This master gave me a good training and knowledge to face real problems concerning renewable energies. I chose photovoltaic solar energy because my major interest in physics are solid state physics and material science, in this manner I could bring together my two passions for material science and green energy. In April 2014, I had the unique chance to go to Institut National de l’Energie Solaire (INES) to make an internship for five month. The principal objective of this internship at Laboratoire de Heterojunction (LHET) in INES was to test the Excimer Laser Annealing (ELA) to improve HET solar cell performance through the amelioration of optical trans...