Glass substrate for Cu-In-Ga-Se solar cell and solar cell using the same

摘要

The glass substrate for a Cu—In—Ga—Se solar cell of the present invention is expressed in mass percentages based on the following oxides, with SiO ₂ being 56 to 63%, Al ₂ O ₃ being 10 to 15%, and B ₂ O ₃ being 0 to 1%, MgO 2.5 to 5%, CaO 3 to 8%, SrO 0 to 4%, BaO 0 to 5%, ZrO ₂ 0.5 to 5%, TiO ₂ 0 to 3% _La 2 _{O 3} and 0-5% 4-8% of Na ₂ O, the _{K 2} O 3 to 8% of Na ₂ O + _{K 2} O containing 10 to _15% SiO 2 -Al ₂ O ₃ is 43% or more and less than 50%, and K ₂ O / Na ₂ O is 1.3 or less. The glass transition temperature is 640 ° C. or higher, the average thermal expansion coefficient is 70 × 10 ^{−7 to} 90 × 10 ⁻⁷ / ° C., and the density is 2.7 g / cm ³ or lower. Moreover, the said glass substrate is used for the solar cell of this invention.