Fabrication of Large Surface Area Semitransparent Monocrystalline Si Solar Cells

An experimental technique is presented for fabricating large surface area semitransparent monocrystalline Si solar cells. The semitransparency is achieved by laser-cutting two-dimensional periodic lattices of ellipses through industrially manufactured Si cells. A novel two-level metal base was invented for minimizing cell breakages during laser cutting. The periodic lattices consist of a large number of ellipses, so as to achieve uniform distribution of the transmitted solar radiation. High efficiencies over 13% are deduced from the I-V curves, recorded under physical sunlight, for all fabricated cells with a 5% transparency.