| 摘要 |
PROBLEM TO BE SOLVED: To realize a solar cell having high performance and high reliability even when a solder coating layer is not contained by forming a surface chemically treated with proper chemicals to an electrode. SOLUTION: The distortion of a surface is removed by etching a P-type silicon substrate 1 and a main surface is formed in a pyramidal irregular shape such as a circular mark 1A, N<+> type impurities are diffused from the substrate 1 by heat treatment to form an N<+> layer 2 and a P-N junction is formed, and an antireflection film 3 is shaped and the unnecessary section of the N<+> diffusion layer 2 is removed. Silver and aluminum paste are screen-printed on the rear of the substrate 1 and baked and rear silver electrodes 4, a rear aluminum electrode 5 and a P<+> layer 6 are formed, and silver paste is screen-printed on the antireflection film 3 and front silver electrodes 7 are shaped. When the substrate 1 is chemically treated with chemicals containing one selected from hydrobromic acid, hydrofluoric acid, DL-malic acid, stearic acid, adipic acid, salicylic acid, citric acid, and lactic acid, the output characteristics of a solar cell can be improved remarkably. |
