In order to provide a nonvolatile semiconductor storage device designed to take
off such existing restraint on the degree of freedom of device design as needed
for the purpose of securing design margin, thus realizing a ferroelectric, nonvolatile
storage device of high integration density, there is disclosed a capacitor using
a ferroelectric thin film is provided, so that the apparent coercive electric field
value in the operational guaranteed margin temperature of the nonvolatile semiconductor
storage device when regarded as the voltage applied to the capacitor remains within
the range of design margin of the nonvolatile semiconductor storage device at the
coercive electric field value at the specified temperature, in which a metal oxide
of a layer structure having the ferroelectric-to-normal dielectric phase transition
point of 800 C. or higher may be used for the ferroelectric thin film.
