MFIS (Metal/Ferroelectrics/Insulator/Silicon) transistor ferroelectric memory devices have been
fabricated. For the small device and high density 1T FeRAM device applications, the selective
deposition processes have been developed to simplify the integration processes and improve the
properties of MFIS transistor ferroelectric memory devices. Based on the different deposition
rates of ferroelectric materials on high-k oxide and silicon dioxide, we can selectively deposit a
c-axis oriented PGO thin film on the patterned high-k oxide such as ZrO
x
(x=0-2), HfO
x
(x=0-
2), TiO
2
, and their mixtures other than on SiO
2
. By patterning the high-k dielectric, the PGO
deposition is limited to just the preferred pattern high-k area. SEM, EDX and x-ray
measurements further confirmed that the c-axis oriented PGO thin films were selectively
deposited on the high-k gate oxide other than on the field SiO
2
. The etching damage is
eliminated since there is no need to etch the PGO film. The properties of 1T MFIS memory
devices are also improved.
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C9.9.6/E9.9.6
3. SUMMARY