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YBa2Cu3O7-δ (YBCO) high temperature superconducting (HTS) thin film is promising in the applications of electric equipments, wind energy generators, electronic devices, etc., attributing to its high performance of current-carrying capacity in magnetic fields.YBCO films could be fabricated via the metal organic deposition method using the trifluoroacetate precursor solution (TFA-MOD), which is regarded as a branch of the sol-gel technology.The heat treatment of YBCO fabrication consists of three steps: pyrolysis, crystallization and oxygenation.In the conventional TFA-MOD process, the pyrolysis step, with temperature ranging from room temperature to 400℃, required a very long duration to avoid the detrimental morphologies such as wrinkling, cracking and blistering, which was caused by the stresses generated along with the decomposition reactions.In this study, the wrinkling morphology of the YBCO thin films with various thickness was formed by a rapid pyrolysis on purpose, and characterized using scanning electron microscopy (SEM) and atomic force microscopy (AFM).The obtained SEM and AFM images was quantitatively analyzed using Matlab to investigate the compressive stress of the pyrolyzed films.The thin film wrinkling mechanisms was also utilized to discuss the influence of film thickness on the average amplitude and wavelength of wrinkling morphology.Moreover, the polymer additive and fluorine content lowering were used to alleviate the stress during the rapid pyrolysis step, and YBCO thin films with critical current density higher than 2 MA/cm2 (77 K, self-field) were prepared.This study could provide more understandings of the stress evolution of YBCO films in the heat treatment, and might be helpful to pave a low-cost path to obtain thin films with tunable wrinkling morphology via the sol-gel method.