A memory including memory cells having active and passive layers may store multiple information bits. The active layer may include an organic polymer that has a variable resistance based on the movement of charged species (ions or ions and electrons) between the passive layer and the active layer. The passive layer may be a super-ionic material that has high ion and electron mobility. The active layer may be self-assembled from a monomer in a liquid or gas.

Memory device with active passive layers

A memory device with multi-bit memory cells and method of making the same uses self-assembly to provide polymer memory cells on the contacts to a transistor array. Employing self-assembly produces polymer memory cells at the precise locations of the contacts of the transistor array. The polymer memory cells change resistance values in response to electric current above a specified threshold value. The memory cells retain the resistivity values over time.

A memory device with a self-assembled polymer film and method of making the same

A novel memory cell is provided with an active region including a molecular system and ionic complexes distributed in the molecular system. A pair of write electrodes are arranged for writing information to the memory cell. The active region is responsive to an electric field applied between the pair of write electrodes for switching between an on state and an off state. The active region has a high impedance in the off state and a low impedance in the on state. A pair of read electrodes is used to detect whether the active region is in the on state or in the off state to read the information from the memory cell. Read electrodes may be made of different materials having different work functions to reduce leakage current.

Molecular memory device

A programmable interconnect structure and method of operating the same provides a programmable interconnection between electrical contacts. The interconnect includes material that has a reversibly programmable resistance. The material includes a molecular matrix with ionic complexes distributed through the molecular matrix. Application of an electrical field or electric current causes the molecular composite material to assume a desired resistivity (or conductivity) state. This state is retained by the molecular composite material to thus form a conductive or a non-conductive path between the electrical contacts.

Reversible field-programmable electric interconnects

A memory cell is provided with a pair of electrodes, and an active layer sandwiched between the electrodes and including a molecular system and ionic complexes distributed in the molecular system. The active layer having a high-impedance state and a low-impedance state switches from the high-impedance state to the low-impedance state when an amplitude of a writing signal exceeds a writing threshold level, to enable writing information into the memory cell. The active layer switches from the low-impedance state to the high-impedance state when an amplitude of an erasing signal having opposite polarity with respect to the writing signal exceeds an erasing threshold level, to enable erasing information from the memory cell.

Molecular memory cell

By ‘writing’ and ‘erasing’ molecule-sized bits of a thin organic film, physicists have demonstrated its potential to become the next high-density storage medium.

Andrew Gannon

Papers

Focus: Toward the Next Generation CD

Toward the Next Generation CD