FABRICATION OF SOLAR CELL

PROBLEM TO BE SOLVED: To simplify the fabrication process of solar cell by forming a coating layer of organic Ti compound containing phosphor on the surface of a substrate and an Al layer on the rear and performing thermal drive-in diffusion on the opposite sides thereby forming an antireflection film of TiO2 and a field layer simultaneously on the surface and rear of substrate, respectively. SOLUTION: A coating layer 3 of organic Ti compound containing phosphor is formed on the surface of an Si substrate 1 and then it is heated and dried. An Al layer 6 is formed on the rear by vacuum deposition. The substrate 1 is then set in a near infrared lamp heating furnace and a heat cycle is started to perform drive-in diffusion simultaneously on the opposite sides thus forming a bond (n+) and an antireflection film 4 of TiO2 on the surface while a field layer (p+) 5 on the rear, respectively. Subsequently, the surface is coated with a silver paste 9 containing n-type dopant while a silver paste 10 containing no dopant is printed on the rear and dried. Finally, it is fired and surface and rear electrodes 7, 8 are formed along with a heavily doped diffusion layer (n+1) 20 and then both electrodes 7, 8 coated with solder thus obtaining a solar cell.