Methods for forming the lower electrode of a capacitor in a semiconductor
circuit, and the capacitors formed by such methods are provided. The
lower electrode is fabricated by forming a texturizing underlayer and
then depositing a conductive material thereover. In one embodiment of a
method of forming the lower electrode, the texturizing layer is formed by
depositing a polymeric material comprising a hydrocarbon block and a
silicon-containing block, over the insulative layer of a container, and
then subsequently converting the polymeric film to relief or porous
nanostructures by exposure to UV radiation and ozone, resulting in a
textured porous or relief silicon oxycarbide film. A conductive material
is then deposited over the texturizing layer resulting in a lower
electrode have an upper roughened surface. In another embodiment of a
method of forming the lower electrode, the texturizing underlayer is
formed by depositing overlying first and second conductive metal layers
and annealing the metal layers to form surface dislocations, preferably
structured as a periodic network. A conductive metal is then deposited in
gaseous phase, and agglomerates onto the surface dislocations of the
texturizing layer, forming nanostructures in the form of island clusters.
The capacitor is completed by depositing a dielectric layer over the
formed lower electrode, and forming an upper capacitor electrode over the
dielectric layer. The capacitors are particularly useful in fabricating
DRAM cells.