Double-sided thin-film solar cell

The invention discloses a double-sided thin-film solar cell. A tellurium magnesium cadmium thin-film solar cell with a wide band gap is prepared on one surface of a transparent substrate of the double-sided thin-film solar cell, a copper indium gallium selenium thin-film solar cell with a narrow band gap is prepared on the other surface of the transparent substrate, the tellurium magnesium cadmium thin-film solar cell comprises a p-type tellurium magnesium cadmium absorption layer and an n-type cadmium sulfide buffer layer, and the copper indium gallium selenium thin-film solar cell comprises a p-type copper indium gallium selenium absorption layer and an n-type cadmium sulfide buffer layer. Two materials with different band gaps are prepared on the two surfaces of the transparent substrate, so that the solar spectrum absorption range is widened, the use ratio of solar radiation energy is increased, and the shortcomings such as lattice mismatch and difficulty in matching photo-generated current of a stacked solar cell are overcome. A tunnel junction is omitted, the two sub cells are prepared on the two surfaces of the transparent substrate respectively, the technical process can be simplified, and the production cost of the solar cell is reduced.