Memory applications of integrated ferroelectric technology

There has been a recent upsurge of activity regarding the integration of ferroelectric capacitors with ICs. This renewed interest is driven, in part, by the potential use of ferroelectric (or paraelectric) thin films as the dielectric in the storage capacitors of 1 Gb density DRAMs. The high relative permittivity of these thin films permits smaller DRAM capacitors and simpler fabrication sequences than standard oxide/nitride dielectrics. In addition, recent advances in the reliability of ferroelectric thin films are causing renewed interest in the use of ferroelectric capacitors as storage elements in nonvolatile memories. Such memories have several potential advantages over current nonvolatile technologies. Ferroelectric memories have write times on the order of 100 ns in contrast to 10 /spl mu/s for FLASH. Ferroelectric memories should endure over 10/sup 12/ write cycles compared to 10/sup 6/ cycles for current FLASH, and ferroelectric capacitors can be programmed at 5 V rather than voltages of 10 V to 20 V required in floating-gate memories.<>