NOVELTY - The superstrate thin film solar cell comprises a first electrode, a light absorption layer (16) comprising a first light absorption layer comprising a group I element-group III element-group VI element compound, a second light absorption layer comprising a group I-element-group III element-group VI element compound and a third light absorption layer comprising a group I element-group III element-group VI element compound, and a second electrode. The first light absorption layer has a band gap, which is less than a band gap of the second light absorption layer.    USE - Used as a superstrate thin film solar cell.    ADVANTAGE - The superstrate thin film solar cell can be effectively manufactured with excellent photoelectric conversion efficiency and improved safety and productivity.    DETAILED DESCRIPTION - The superstrate thin film solar cell comprises a first electrode, a light absorption layer (16) comprising a first light absorption layer comprising a group I element-group III element-group VI element compound, a second light absorption layer comprising a group I-element-group III element-group VI element compound and a third light absorption layer comprising a group I element-group III element-group VI element compound, and a second electrode. The first light absorption layer has a band gap, which is less than a band gap of the second light absorption layer, where a band gap of the second light absorption layer is less than a band gap of the third light absorption layer. The second light absorption layer has a band gap gradient, which increases in a direction from the first light absorption layer to the third light absorption layer. The first, second and third light absorption layers have a band gap of 1-3 electron-volts. The first and third light absorption layers have a thickness of 0.1-0.8 mm, and the second light absorption layer has a thickness of 0.3-2 mm. The first light absorption layer is arranged on the second light absorption layer, and the second light absorption layer is arranged on the third light absorption layer. An INDEPENDENT CLAIM is included for a method for manufacturing a thin film solar cell.    DESCRIPTION OF DRAWING(S) - The diagram shows a schematic cross-sectional view of a thin film solar cell.    Substrate (12)    Rear electrode (14)    Light absorption layer (16)    Buffer layer (18)    Front electrode. (20)