학술논문

A 1.6 GB/s DDR2 128 Mb Chain FeRAM With Scalable Octal Bitline and Sensing Schemes
Document Type
Periodical
Source
IEEE Journal of Solid-State Circuits IEEE J. Solid-State Circuits Solid-State Circuits, IEEE Journal of. 45(1):142-152 Jan, 2010
Subject
Components, Circuits, Devices and Systems
Engineered Materials, Dielectrics and Plasmas
Computing and Processing
Random access memory
Ferroelectric films
Nonvolatile memory
Parasitic capacitance
Clocks
CMOS process
Bandwidth
SDRAM
Current supplies
Timing
FeRAM
ferroelectric memory
nonvolatile memory
RAM
random access memory
Language
ISSN
0018-9200
1558-173X
Abstract
An 87.7 ${\hbox {mm}}^{2}$ 1.6 GB/s 128 Mb chain FeRAM with 130 nm 4-metal CMOS process is demonstrated. In addition to small bitline capacitance inherent to chain FeRAM architecture, three new FeRAM scaling techniques—octal bitline architecture, small parasitic capacitance sensing scheme, and dual metal plateline scheme—reduce bitline capacitance from 100 fF to 60 fF. As a result, a cell signal of $\pm$220 mV is achieved even with the small cell size of 0.252 $ \mu{\hbox{m}}^{2}$. An 800 Mb/s/pin read/write bandwidth at 400 MHz clock is realized by installing SDRAM compatible DDR2 interface, and performance is verified by simulation. The internal power-line bounce noise due to 400 MHz clock operation is suppressed to less than 50 mV by an event-driven current driver, which supplies several hundreds of mA of current within 2 ns response. The precise timing and voltage controls are achieved by using the data stored in a compact FeRAM-fuse, which consists of extra FeRAM memory cells placed in edge of normal array instead of conventional laser fuse links. This configuration minimizes area penalty to 0.2% without cell signal degradation.