NOVELTY - Fabricating e.g. nanostructure PN junction diode array thin-film solar cell comprises: providing source-material wafer having semiconductor e.g. nanostructure array (11); coating N-type semiconductor (31) on first transparent substrate (30); making array contact with N-type semiconductor; fusing together N-type semiconductor and a side of array; detaching and transferring array to first transparent substrate; coating P-type semiconductor (41) on second transparent substrate (40); making array contact with P-type semiconductor; and fusing together P-type semiconductor and another side of array.    USE - The method is useful for fabricating micro/nanostructure PN junction diode array thin-film solar cell.    ADVANTAGE - The method: provides a flexible, lower-cost, high photoelectric conversion efficiency, and larger-area thin film solar cell; fabricates the diode array of the thin-film solar cell via etching a high-crystallinity chip, thus produces a fine-quality semiconductor material; and reuses semiconductor substrate, thus can save lot of semiconductor material.    DETAILED DESCRIPTION - Fabricating a micro/nanostructure PN junction diode array thin-film solar cell, comprises: providing a source-material wafer having a semiconductor micro/nanostructure array (11); coating a thin-film N-type semiconductor (31) on a first transparent substrate (30); making the semiconductor micro/nanostructure array contact with the thin-film N-type semiconductor of the first transparent substrate; fusing together the thin-film N-type semiconductor and one side of the semiconductor micro/nanostructure array; detaching the semiconductor micro/nanostructure array and transferring the semiconductor micro/nanostructure array to the first transparent substrate; coating a thin-film P-type semiconductor (41) on a second transparent substrate (40); making the semiconductor micro/nanostructure array contact with the thin-film P-type semiconductor of the second transparent substrate; and fusing together the thin-film P-type semiconductor and another side of the semiconductor micro/nanostructure array to form the micro/nanostructure PN junction diode array thin-film solar cell.    DESCRIPTION OF DRAWING(S) - The figure shows schematic view of several micro/nanostructure PN junction diodes array thin-film solar cells.    Semiconductor micro/nanostructure array (11)    First transparent substrate (30)    Thin-film N-type semiconductor (31)    Second transparent substrate (40)    Thin-film P-type semiconductor (41)