A long life ferroelectric memory device using a thin ferroelectric film capacitor
as a memory capacitor is obtained by disposing a plurality of degradation preventive
layers on an upper protection electrode and an upper electrode 8 and a degradation
preventive layer at the boundary of ferroelectric layer 7/electrodes 6,
8, or providing a step of decreasing a modified layer at the boundary of ferroelectric
layer 7/upper electrode 8. This provides a thin ferroelectric film
capacitor which is subjected to less fatigue and imprinting and which has less
degradation of ferroelectric characteristic to attain a long life ferroelectric
memory device.
