Abstract: An improved architecture and method for operating a PCRAM integrated circuit is disclosed which seeks to minimize degradation in the resistance of the phase change material in the cells. When an attempt is made during a write command to write a data state to a bit which already has that data state, such matching data states are identified and writing to those bits is precluded during the write command. In one embodiment, both the incoming data to be written to a bit and the data currently present at that bit address are latched. These latched data are then compared (e.g., with an XOR gate) to determine which bits have a matching data state. The results of this comparison are used as an enable signal to the write (column) driver in the PCRAM memory array, with the effect that only data bits having different data state are written, while data bits having a matching data state are not needlessly re-written.

Abstract: A method of forming a metal cap over a conductive interconnect in a chalcogenide-based memory device is provided and includes, forming a layer of a first conductive material over a substrate, depositing an insulating layer over the first conductive material and the substrate, forming an opening in the insulating layer to expose at least a portion of the first conductive material, depositing a second conductive material over the insulating layer and within the opening, removing portions of the second conductive material to form a conductive area within the opening, recessing the conductive area within the opening to a level below an upper surface of the insulating layer, forming a cap of a third conductive material over the recessed conductive area within the opening, depositing a stack of a chalcogenide based memory cell material over the cap, and depositing a conductive material over the chalcogenide stack.

Abstract: An improved architecture and method for operating a PCRAM integrated circuit is disclosed which seeks to minimize degradation in the resistance of the phase change material in the cells. When an attempt is made during a write command to write a data state to a bit which already has that data state, such matching data states are identified and writing to those bits is precluded during the write command. In one embodiment, both the incoming data to be written to a bit and the data currently present at that bit address are latched. These latched data are then compared (e.g., with an XOR gate) to determine which bits have a matching data state. The results of this comparison are used as an enable signal to the write (column) driver in the PCRAM memory array, with the effect that only data bits having different data state are written, while data bits having a matching data state are not needlessly re-written.

Abstract: An improved architecture and method for operating a PCRAM integrated circuit is disclosed which seeks to minimize degradation in the resistance of the phase change material in the cells. When an attempt is made during a write command to write a data state to a bit which already has that data state, such matching data states are identified and writing to those bits is precluded during the write command. In one embodiment, both the incoming data to be written to a bit and the data currently present at that bit address are latched. These latched data are then compared (e.g., with an XOR gate) to determine which bits have a matching data state. The results of this comparison are used as an enable signal to the write (column) driver in the PCRAM memory array, with the effect that only data bits having different data state are written, while data bits having a matching data state are not needlessly re-written.

Abstract: An improved architecture and method for operating a PCRAM integrated circuit is disclosed which seeks to minimize degradation in the resistance of the phase change material in the cells. When an attempt is made during a write command to write a data state to a bit which already has that data state, such matching data states are identified and writing to those bits is precluded during the write command. In one embodiment, both the incoming data to be written to a bit and the data currently present at that bit address are latched. These latched data are then compared (e.g., with an XOR gate) to determine which bits have a matching data state. The results of this comparison are used as an enable signal to the write (column) driver in the PCRAM memory array, with the effect that only data bits having different data state are written, while data bits having a matching data state are not needlessly re-written.

Abstract: A method of forming a metal cap over a conductive interconnect in a chalcogenide-based memory device is provided and includes, forming a layer of a first conductive material over a substrate, depositing an insulating layer over the first conductive material and the substrate, forming an opening in the insulating layer to expose at least a portion of the first conductive material, depositing a second conductive material over the insulating layer and within the opening, removing portions of the second conductive material to form a conductive area within the opening, recessing the conductive area within the opening to a level below an upper surface of the insulating layer, forming a cap of a third conductive material over the recessed conductive area within the opening, the third conductive material selected from the group consisting of cobalt, silver, gold, copper, nickel, palladium, platinum, and alloys thereof, depositing a stack of a chalcogenide based memory cell material over the cap, and depositing a cond

Abstract: A method of providing a planar or iso-planar surface to the interlevel dielectric layer between metal layers of a multilevel MOS wafer includes applying a first dielectric over the first metal layer, applying a layer of spin-on glass over the first dielectric layer, etching the spin-on glass layer in an etch process in which the rate of etch of the spin-on glass is approximately the same as the rate of etch of the first dielectric to reveal at least a portion of the first dielectric layer. A second dielectric layer is placed over the surface of the first dielectric. Vias may then be defined through the dielectric layers, and the second metal layer may be applied over the relatively smooth surface of the second dielectric layer.