NOVELTY - The method comprises forming a first conductive layer (120) on a substrate (110), dissolving an organic active semiconductor material and a functional organic material in an organic solvent to form a blend, depositing the blend on the first conductive layer, removing the organic solvent such that the functional organic material and the organic active semiconductor material exhibit a phase separation to form an organic modified layer (134) and an organic active semiconductor layer (132), and forming a second conductive layer on the organic modified layer.    USE - The method is useful for manufacturing a polymer solar cell.    ADVANTAGE - The method is capable of simply and economically manufacturing the impact resistant polymer solar cell with excellent and stable energy conversion efficiency, reduced weight, superior flexibility, high performance and improved lifespan in less number of processing steps.    DETAILED DESCRIPTION - The method comprises forming a first conductive layer (120) on a substrate (110), dissolving an organic active semiconductor material and a functional organic material in an organic solvent to form a blend, depositing the blend on the first conductive layer, removing the organic solvent such that the functional organic material and the organic active semiconductor material exhibit a phase separation to form an organic modified layer (134) and an organic active semiconductor layer (132), and forming a second conductive layer on the organic modified layer. The organic active semiconductor layer is sandwiched between the organic modified layer and the first conductive layer. A content of the functional organic material in the blend is less than 5 wt.% of the blend. The step of depositing the blend on the first conductive layer comprises spin coating, inkjet-printing, screen-printing, doctor-blade coating and spray-coating. The organic active semiconductor material comprises a mixed semiconductor material constituted by an n-type semiconductor material and a p-type semiconductor material. A material of the second conductive layer comprises a material featuring high work function. The step of forming the second conductive layer comprises evaporation. The step of removing the organic solvent comprises evaporating the organic solvent. The step of forming the first conductive layer comprises forming an electrode layer on the substrate, and forming a conductive polymer layer on the electrode layer. An INDEPENDENT CLAIM is included for a polymer solar cell.    DESCRIPTION OF DRAWING(S) - The diagram shows a cross-sectional view of a process of manufacturing a polymer solar cell.    Polymer solar cell (100)    Substrate (110)    First conductive layer (120)    Organic active semiconductor layer (132)    Organic modified layer. (134)