A dielectric region, such as a ferroelectric dielectric region of an integrated
circuit capacitor, is protected by a multi-layer insulation structure including
a first relatively thin insulation layer, e.g., an aluminum oxide or other metal
oxide layer, and a second, thicker insulating layer, e.g., a second aluminum oxide
or other metal oxide layer. Before formation of the second insulation layer, the
first insulation layer and the dielectric preferably annealed, which can increase
a remnant polarization of the dielectric region. The first insulation layer can
serve as a hydrogen diffusion barrier during formation of the second insulation
layer and other overlying structures. In this manner, degradation of the dielectric
can be reduced. Devices and fabrication methods are discussed.