A semiconductor memory device is described that can, in certain embodiments, reduce a delay in access time andor an area of a memory cell array. Lead-free solder becomes practical for use since the temperature for reliable soldering is reduced. An amorphous layer containing the elemental metal and elemental oxygen that constitute the ferroelectric is formed over the titanium layer, and a crystallized ferroelectric thin film is formed by heat treating this amorphous layer. An update procedure acts on the restored data concurrently with the restoration procedure. The magnetoresistance effect device 1 and the magnetoresistance effect type magnetic head 20, thus constructed, exhibit a magnetoresistance effect when fed with the sense current without destructing the antiferromagnetic coupling.