▎ 摘　　要

NOVELTY - Preparation of a perovskite film with a surface compressive stress-enhancing structure involves forming a perovskite precursor solution layer coated on a substrate by rapid heating-quenching. The maximum heating rate of the perovskite precursor solution layer is 10-500° C/second and maximum cooling rate of the perovskite film is 15-500° C/second, or the time of rapid heating is 0.1-10 seconds, temperature is increased to 30-250° C, the time of rapid quenching is 0.1-10 seconds, and the temperature is lowered to 30-250° C. USE - Preparation of perovskite thin film used as active layer of solar cell for light-emitting device (all claimed). ADVANTAGE - The method produces perovskite thin film having excellent optical physical property, such as ultra-long exciton transmission length, high absorption coefficient in the visible spectrum range, and less deep level defect. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: a perovskite crystal grain or the perovskite film containing the perovskite crystal grain; and a solar cell.