Polyimide film-soda glass composite substrate and preparation method thereof

A polyimide film-soda glass composite substrate is formed by soda glass and a polyimide film growing on the surface of the soda glass, wherein the thickness of the soda glass is 1.5-2mm, and the thickness of the polyimide film is 25-30 micrometers. The preparation method of the polyimide film-soda glass composite substrate includes that polyimide glue coats the surface of the soda glass, and after glue evening and curing processes, the polyimide film-soda glass composite substrate is obtained. The polyimide film-soda glass composite substrate and the preparation method have the advantages that the polyimide film-soda glass composite substrate and copper indium gallium selenium absorption layer have almost perfectly matched heat expansion coefficients, after a complete copper indium gallium selenium solar cell is prepared, the copper indium gallium selenium solar cell is separated from the soda glass, the flexible copper indium gallium selenium solar cell making the polyimide film as a substrate is formed, and possibility is provided for preparation of the flexible solar cell by means of the steel substrate; the preparation method is simple and easy to implement and beneficial to large-scale popularization and application, and has extremely important application prospects in the outer space and on special occasions.