PURPOSE: To give the conditions of a temperature and a pressure for forming a thin film capable of growing in the orientation relation of a cube on cube in which an SrTiO3 layer is on an MgO plane (001) in a board structure in which the SrTiO3 layer is formed on a single crystalline surface of the MgO (001).

CONSTITUTION: An orientation of cube on cube is obtained on a hatched temperature-pressure area 11, an orientation (110) is mainly grown in a region 12, and an orientation (111) is mainly grown in a region 13. Accordingly, a low-cost perovskite structure board having a large area is given with suitable thin film growth of an oxide superconductor, a ferroelectric element, etc.