Yoriaki Nagata

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We propose Bit-Cost Scalable (BiCS) technology which realizes a multi-stacked memory array with a few constant critical lithography steps regardless of number of stacked layer to keep a continuous reduction of bit cost. In this technology, whole stack of electrode plate is punched through and plugged by another electrode material. SONOS type flash(More)
We propose pipe-shaped bit cost scalable (P-BiCS) flash memory which consists of pipe-shaped NAND strings folded like a u-shape instead of the straight-shape. P-BiCS flash technology achieves a highly reliable memory film of which the program and erase (P/E) operation is managed by Fowler-Nordheim (FN) tunneling, that is originated by the strong curvature(More)
Optimal process integration for array devices of bit-cost scalable (BiCS) flash memory is successfully developed. We adopt SiN-based gate dielectrics for the consistency with the 'gate-first' process which is unique to BiCS flash technology, and 'macaroni' body FETs for better controllability over the sub-threshold characteristics of depletion-mode(More)
Program and erase operation on NAND-string of Bit-Cost Scalable (BiCS) flash memory has been successfully achieved. High boost efficiency of floating pillars and ONON (block oxide/charge SiN/tunnel oxide/tunnel SiN) structure as a memory film stack improve disturbance characteristics enough to realize tera-bit density of three dimensional flash memory. BiCS(More)
Novel vertex channel array transistor (VCAT) fabricated on bulk silicon substrate is applied to trench capacitor DRAM cell for the first time. VCAT utilizes the vertexes as channel between top surface and (111) facet of selective epitaxial Si on active areas. It can be fabricated with much simpler process than FIN array transistor reported previously and(More)
Vertex channel (VC) transistor is applied to both support devices and array transistor of trench capacitor DRAM for the first time. On-current of VC-FETs is much higher than that of conventional planar devices with keeping sufficiently small off-current. They achieve 15% or much smaller propagation delay (Tpd) of fan-out 3 than planar devices. Furthermore,(More)
Reliability becomes one of the most important issues for designing LSIs. Negative bias temperature instability (NBTI) is a phenomenon in which the performance of a transistor deteriorates depending on the temperature and the transistor switching frequency. In the manufacturing process generations of 32 nm and 22 nm, it will be expected that timing(More)
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