Abstract We report a novel doping strategy for YBa2Cu3O7-x (YBCO) superconducting films by using positive mismatch, Ba2YNbO6 (BYNO), and negative LaAlO3 (LAO), simultaneously. Double can significantly reduce the c-strain in YBCO film canceling strain between two dopants. By systematically optimizing amount of both BYNO LAO, it was found that LAO do not act equally. The microstructure distributi...