Abstract: A memory cell including a phase-change material may have reduced leakage current. The cell may receive signals through a buried wordline in one embodiment. The buried wordline may include a sandwich of a more lightly doped N type region over a more heavily doped N type region over a less heavily doped N type region. As a result of the configuration of the N type regions forming the buried wordline, the leakage current of the buried wordline to the substrate under reverse bias conditions may be significantly reduced.

Abstract: A memory or switching device includes a mesa and a first electrode conforming to said mesa. The device also includes a second electrode and a phase-change or switching material disposed between said first and second electrodes. The phase-change or switching material is in electrical communication with the first and second electrodes at a first contact region and a second contact region respectively. Also described is a method for making a memory or switching device. The method includes providing a first insulator and configuring the first insulator to provide a mesa. A first conductive layer is provided conforming to the mesa. A phase-change or switching material is provided over a portion of the first conductive layer, and a second conductive layer is provided over the phase-change or switching material.

Abstract: A radial memory device includes a phase-change material, a first electrode in electrical communication with the phase-change material, the first electrode having a substantially planar first area of electrical communication with the phase-change material. The radial memory device also includes a second electrode in electrical communication with the phase-change material, the second electrode having a second area of electrical communication with the phase-change material, the second area being laterally spacedly disposed from the first area and substantially circumscribing the first area. Further, a method of making a memory device is disclosed. The steps include depositing a first electrode, depositing a first insulator, configuring the first insulator to define a first opening. The first opening provides for a generally planar first contact of the first electrode.

Abstract: A non-volatile memory device includes a lower electrode, a phase-change material layer formed on the lower electrode so as to be electrically connected to the lower electrode, and an upper electrode formed on the phase-change material layer so as to be electrically connected to the phase-change material layer. The phase-change material layer includes a phase-change material including a composition represented by the formula (I)A(IIXIIYIVZ)(1-A), where I is at least one of As and Se, II is at least one of Ge, Si and Sn, III is at least one of Sb and Bi, and IV is at least one of Te and Se, and where 0.001?A?0.3, 0.001?X?0.3, 0.001?Y?0.8, 0.1?Z?0.8, and X+Y+Z=1.

Abstract: A memory may be implemented with a stable chalcogenide glass which is defined as a generally amorphous chalcogenide material that does not change to a generally crystalline phase when exposed to 200° C. for 30 minutes or less. Different states may be programmed by changing the threshold voltage of the material. The threshold voltage may be changed with pulses of different amplitude and/or different pulse fall times. Reading may be done using a reference level between the threshold voltages of the two different states. A separate access device is generally not needed.

Abstract: A standalone memory device includes thin-film peripheral circuitry, including decoding circuitry. The standalone thin film memory excludes all single-crystal electronic devices and may be formed, for example, on a low-cost substrate, such as fiberglass. The memory is configured for operation with an external memory controller.

Abstract: A chemical vapor deposition (CVD) process for preparing electrical and optical chalcogenide materials. In a preferred embodiment, the instant CVD-deposited materials exhibit one or more of the following properties: electrical switching, accumulation, setting, reversible multistate behavior, resetting, cognitive functionality, and reversible amorphous-crystalline transformations. In one embodiment, a multilayer structure, including at least one layer containing a chalcogen element, is deposited by CVD and subjected to post-deposition application of energy to produce a chalcogenide material having properties in accordance with the instant invention. In another embodiment, a single layer chalcogenide material having properties in accordance with the instant invention is formed from a CVD deposition process including three or more deposition precursors, at least one of which is a chalcogen element precursor. Preferred materials are those that include the chalcogen Te along with Ge and/or Sb.

Abstract: A phase change memory cell may be read by driving a current through the cell higher than its threshold current. A voltage derived from the selected column may be utilized to read a selected bit of a phase change memory. The read window or margin may be improved in some embodiments. A refresh cycle may be included at periodic intervals.

Abstract: A three-dimensional memory array formed of one or more two-dimensional memory arrays of one-time programmable memory elements arranged in horizontal layers and stacked vertically upon one another; and a two-dimensional memory array of reprogrammable phase change memory elements stacked on the one or more two-dimensional memory arrays as the top layer of the three-dimensional memory array.

Abstract: The invention provides a memory cell based on variable resistance material memory element that includes an access device having a pillar structure that may also include a protective sidewall layer. The pillar access device selects and isolates the memory cell from other memory array cells and is adapted to both self-align any memory element formed thereon, and to deliver suitable programming current to the memory element. The pillar structure is formed from one or more access device layers stacked above a wordline and below the memory element. Optional resistive layers may be selectively formed within the pillar structure to minimize resistance in the access device layer and the memory element. The pillar access device may be a diode, transistor, Ovonic threshold switch or other device capable of regulating current flow to an overlying programmable memory material.

Abstract: An electronic system includes at least one reduced-complexity integrated circuit memory coupled to a memory controller. By reducing the complexity of each integrated circuit memory and concentrating the complexity within the memory controller, overall system costs may be greatly reduced and reliability improved.

Abstract: A chalcogenide material is proposed for programming the cross-connect transistor coupling interconnect lines of an electrically programmable matrix array. Leakage may be reduced by optionally placing a thin insulating breakdown layer in series with the select device or a phase change material. The matrix array may be used in a programmable logic device.

Abstract: A multilevel phase change memory may be formed of a chalcogenide material formed between a pair of spaced electrodes. The cross-sectional area of the chalcogenide material may decrease as the material extends from one electrode to another. As a result, the current density decreases from one electrode to the other. This means that a higher current is necessary to convert the material that has the largest cross-sectional area. As a result, different current levels may be utilized to convert different amounts of the chalcogenide material to the amorphous or reset state. A distinguishable resistance may be associated with each of those different amounts of amorphous material, providing the opportunity to engineer a number of different current selectable programmable states.

Abstract: A programmable resistance memory element. The active volume of memory material is made small by the presence of a small area of contact between the conductive material and the memory material. The area of contact is created by forming a region of conductive material and an intersecting sidewall layer of the memory material. The region of conductive material is preferably a sidewall layer of conductive material.

Abstract: Fixed-voltage programming pulses are employed to program a phase change memory cell. A burst of incrementally widening fixed-voltage programming pulses may be employed to program a phase change memory to a target threshold voltage.

Abstract: A phase change device may be formed by forming a phase change material and an electrode in a pore in an insulator. The phase change material fills less of the pore than the electrode.

Abstract: A memory is configurable among a plurality of operational modes and types of interfaces. The operational modes may dictate the number of storage levels to be associated with each cell within the memory's storage matrix. Individual operational modes may be matched to individual interfaces, operated one at a time or in parallel.

Abstract: Briefly, in accordance with an embodiment of the invention, a method to manufacture a phase change memory is provided. The method may include forming a first electrode contacting the sidewall surface and the bottom surface of the phase change material. The method may further include forming a second electrode contacting the top surface of the phase change material.

Abstract: A chalcogenide material and chalcogenide memory device having less stringent requirements for formation, improved thermal stability and/or faster operation. The chalcogenide materials include materials comprising Ge, Sb and Te in which the Ge and/or Te content is lean relative to the commonly used Ge2Sb2Te5 chalcogenide composition. Electrical devices containing the instant chalcogenide materials show a rapid convergence of the set resistance during cycles of setting and resetting the device from its as-fabricated state, thus leading to a reduced or eliminated need to subject the device to post-fabrication electrical formation prior to end-use operation. Improved thermal stability is manifested in terms of prolonged stability of the resistance of the device at elevated temperatures, which leads to an inhibition of thermally induced setting of the reset state in the device. Significant improvements in the 10 year data retention temperature are demonstrated.

Abstract: A memory employs a low-level current source to access a phase change memory cell. The current source charges an access capacitor in order to store sufficient charge for an ensuing access. When a memory cell is accessed, charge stored on the capacitor is discharged through the phase change memory, supplying a current to the phase change memory cell that is sufficient for the intended access operation and greater than that provided directly by the current source.