Patent ID: 7232764

Claim:
A semiconductor device fabrication method comprising the steps of: forming over a semiconductor substrate a ferroelectric capacitor including a lower electrode, a ferroelectric film formed over the lower electrode, and a upper electrode formed over the ferroelectric film; forming a first insulation film over the semiconductor substrate and the ferroelectric capacitor; forming a first interconnection over the first insulation film; forming a second insulation film over the first insulation film and the first interconnection; planarizing a surface of the second insulation film; making heat treatment with a heat treatment furnace to remove water from the second insulation film; making heat treatment in a plasma atmosphere generated by using N 2 O gas or N 2 gas to remove water from the second insulation film and nitride the surface of the second insulation film; forming over the second insulation film a first flat barrier film for preventing the diffusion of hydrogen or water; forming a first contact hole in the first barrier film and the second insulation film down to the first interconnection; and burying a first conductor plug in the first contact hole.