The manufacturing of high-density ferroelectric memories or DRAM memor
ies with high-dielectric constant materials in sub-micron IC processes
demands for a technology where the capacitor is directly contacted fr
om below to the access transistor. In this paper such a technology, ba
sed on a sub-micron IC process with planarization and tungsten plugs,
is described. The risk of deterioration of the CMOS circuitry (in part
icular the oxidation of contacts) is successfully prevented by using a
Ru/RuPt bottom electrode for the ferroelectric capacitors. With this
electrode no increase of contact resistances nor degradation of CMOS c
haracteristics are found after the ferroelectric processing, using a P
bZrxT1-xO3 film deposited by organometallic chemical vapour deposition
at 700 degrees C. The properties of direct-contact capacitors are goo
d.