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16M FeRAM was successfully developed using a (Bi 1−X La X ) 4 Ti 3 O 12 , BLT, film with excellent imprint characteristic as a ferroelectric film to decrease capacitor size, current gain cell operation (CGCO) sensing scheme, and split word line (SWL) cell array architecture with hierarchical-double bit line in order to increase cell array efficiency. The chip size of 16M FeRAM could be reduced down to about 63% compared with a conventional one by the adoption of the novel ferroelectric material and the design architectures. The read/write access time and cycle time are 70 ns and 100 ns in operation voltage of 3.0 at room temperature, respectively. The operation and standby current are less than 20 mA and 10 µA, respectively.

Gettering efficiencies of copper, whose bulk concentrations are lower than 1 ϫ 10 12 atoms/cm 3 in p-type silicon, have been evaluated quantitatively and the results are reported. Bulk copper introduced by intentional spiking and subsequent heat-treatment was shown to be gettered by bulk microdefects ͑BMDs͒, which had been introduced by heat-treatment prior to intentional contamination using a 65 Cu isotope tracer as a probe. For evaluation of gettering efficiencies, we found the trace analysis of the 65 Cu isotope to be critical and, thus, developed a procedure for trace analysis of bulk copper in the silicon bulk by modifying the published analytical technique, which allowed gettering efficiencies to be quantitatively evaluated for copper levels of below 10 12 atoms/cm 3 . We also describe a few other parameters important to the evaluation of gettering efficiencies, including outdiffusion of copper through the silicon matrix, formation of BMDs, and low-temperature out-diffusion.

A fully integrated passive and battery powered semi-active UHF RFID transponder chip supporting EPC Gen 2 protocol is presented. The proposed transponder works as a passive RFID tag when the generated RF-power is sufficient to operate, otherwise it operates in semi-active mode using battery power. The chip has re-writeable non-volatile memory bank formed by FeRAM and on-chip temperature sensor. The memory consists of EPC memory bank for EPC functionality and temperature bank for storing sensed data. The standby current in semi-active is about 0.5uA, the lifetime in semi-active mode is in excess of 2 year with a 10mA-hr thin film battery.

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