摘要 |
The tin-free air side of each of float-processed soda-lime float glass substrates is quickly and accurately distinguished, and the substrates are arranged, with the air sides facing upward. CIS based thin-film photovoltaic devices are formed on the air sides to improve conversion efficiency and yield and reduce production cost. A surface of a glass substrate is irradiated with ultraviolet lights. When fluorescence occurs, this side is judged to be the tin-containing float side B (P1) and a tin containment mark is put thereon (P2). When the upper side is the air side A not bearing a tin containment mark, this substrate is subjected as it is to a cleaning/drying step and to the formation of a CIS based thin-film photovoltaic device on the air side A. When the upper side is the float side B, this substrate is turned over (P3) and then subjected to a cleaning/drying step (P4) and to the formation of a CIS based thin-film photovoltaic device on the upper side, i.e., the air side A (P5). |