NOVELTY - A gallium arsenide thin-film multijunction stacked solar cell manufacturing method involves allowing for reverse growth of an epitaxial layer to obtain a gallium arsenide three-junction solar cell. The three-junction solar cell is bonded to a silicon substrate. A germanium substrate is stripped. A low-cost substrate is adhered and the silicon substrate is stripped, where the solar cell has gallium indium phosphide corrosion stopping layer, n-type doped gallium arsenide cap layer, a first tunnel junction, a second tunnel junction and n-type doped indium aluminum gallium arsenide graded layer.    USE - Method for manufacturing a gallium arsenide thin-film multijunction stacked solar cell.    ADVANTAGE - The method enables facilitating epitaxial growth of a top cell and an intermediate cell prior to growth of a bottom cell, improving doping uniformity and film reliability in large-area epitaxial thin films, improving photoelectric conversion efficiency of the solar cell, reducing the weight of the cell by using the low-cost support substrate lower than germanium in specific weight, increasing the power ratio of the solar cell, effectively reducing the cost of the cell, and improving application prospect of the III-V compound solar cell.    DETAILED DESCRIPTION - A gallium arsenide thin-film multijunction stacked solar cell manufacturing method involves allowing for reverse growth of an epitaxial layer to obtain a gallium arsenide three-junction solar cell, where the growth temperature is 500-800 degrees C and the epitaxial growth thickness is 0.1-0.3 mu m. The three-junction solar cell is bonded to a silicon substrate. A germanium substrate is stripped. A low-cost substrate is adhered and the silicon substrate is stripped, where the stacked solar cell has gallium indium phosphide corrosion stopping layer with thickness of 100-500 nm, n-type doped gallium arsenide cap layer, a first tunnel junction, a second tunnel junction, and n-type doped indium aluminum gallium arsenide (Inx(AlyGa1-y)1-xAs) graded layer with thickness of 2-5 mu m, and a bottom cell of indium gallium arsenide (InxGa1-xAs) graded layer, x is 0.03-0.3, y is 0.5-0.7 and n is 1x 1017-1x 1018 cm-3.    DESCRIPTION OF DRAWING(S) - The drawing shows a sectional view of a gallium arsenide thin-film multijunction stacked solar cell. '(Drawing includes non-English language text)'