To keep the surface of a lower electrode free from abnormal deposit and concentration of an electric field so as to improve a dielectric thin film element in dielectric strength, fatigue resistance, and permittivity by a method wherein a lower electrode is formed of Pt which contains at least one out of elements Rh, Ru, Os, and Ir.

A lower electrode 54 of Pt which contains, at least, one out of elements Rh, Ru, Os, and Ir is formed on a board 51. Moreover, a high dielectric or a ferroelectric film 55 and an upper electrode 56 are formed thereon. No hillock is deposited on the surface of the lower electrode 54 even if the device of this constitution is subjected to a thermal treatment carried at a temperature of 600°C or above, so that the surface of the lower electrode 54 is kept flat, and the growth of nucleuses takes place well at the heat treatment of the high dielectric or the ferroelectric film 55, so that defects are prevernted from being generated. Abnormal deposits such as hillocks are not present on the surface of the lower electrode 54, so that an electric field is restrained from concentrating locally when a voltage is applied between the electrodes 54 and 56, and the device of this constitution can be improved in dielectric strength and fatigue resistance.