Ferroelectric memories

Inside story of ferroelectric memories.
Vincent Garcia and Manuel Bibes
483279a.pdf (application/pdf Object)

See also the previous entry: Ferroelectric solid state memories

Binary and multilevel data storage. a, In a classical binary ferroelectric random access memory (FERAM), a bit of information, with a logic value of ‘1’ or ‘0’, is encoded in the up (red block) or down (blue block) polarization direction of the device’s constituent cells. In this 36-bit example, the bits are stored in 6 × 6 cells, each of which stores one bit. Electrical wires (grey) are used to apply voltages across the cells to write and read the cells’ polarization. b, Lee et al.3 describe a multilevel FERAM that can store three bits in a single cell. In this way, three-bit logic states (000, 001, 010, 011, 100, 101, 110 and 111) can be stored in each of 3 × 4 cells of a smaller 36-bit memory array. Each state corresponds to a specific configuration of domains of opposite polarization in the cells.