This paper describes our circuit technologies that can be used to obtain fa
st and large-capacity FeRAMs with high reliability. The Non-driven Cell Pla
te Line Write/Read Scheme (NDP Scheme) offers a fast access time equivalent
to that of DRAMs. This scheme makes it possible to access memory cells wit
hout having to drive the highly capacitive cell plate line, thus reducing w
rite/read delay time. The Self-Reference Read Scheme is used to produce hig
hly reliable FeRAMs, because it avoids the read voltage fluctuation, due to
fatigue, imprint, and insufficient retention in the ferroelectric capacito
rs, between an accessed memory cell and the corresponding dummy memory cell
. These technologies are essential for mega-bit-class FeRAMs.