Abstract: Providing a multiplexor outputting a reference voltage on unselected lines. A multiplexor that has at least one selected line and multiple unselected lines will have the unselected lines at a reference voltage. The selected line allows at least a portion of voltage to pass. Two gate circuits are used for each line, one that controls whether voltage (or a portion thereof) will pass, the other that connects the first gate circuit to a reference voltage, such as ground. In some embodiments the second gate circuit is always on, but is relatively small, such that the connection to the reference voltage has a weak effect on the output voltage. In other embodiments, the second gate circuit is only on when its associated first gate circuit is off.

Abstract: High density NVRAM. The invention is a an array of memory cells capable of storing at least a megabit of information, each memory cell including a memory plug that includes a memory element that switches from a first resistance state to a second resistance state upon application of a first write voltage of a first polarity and reversibly switches from the second resistance state to the first resistance state upon application of a second write voltage of polarity opposite to the first polarity.

Abstract: Providing a reference voltage to a cross point memory array. The invention is a cross point memory array and some peripheral circuitry that, when activated, provides a reference voltage to a cross point array in order to prevent unselected conductive array lines from floating to an undesired voltage. The peripheral circuitry can be activated before, after or during selection of a specific memory plug. If the peripheral circuitry is activated during selection, only the unselected conductive array lines should be brought to the reference voltage. Otherwise, all the conductive array lines can be brought to the reference voltage.

Abstract: Providing a multi-output multiplexor. The invention is multi-output multiplexor that, depending on the control signals, allows various modulating circuits to pass no voltage, pass some voltage or pass all the voltage on one of the mulitplexor's ports., A modulating circuit can be fully turned on, partially turned on, or fully turned off. In a preferred embodiment, a gate circuit is in electrical contact with ground such that when the gate circuit is turned on and its associated modulating circuit is not passing voltage, the multiplexor output associated with the modulating circuit goes to ground.

Abstract: Cross point memory array using multiple modes of operation. The invention is a cross point memory array that uses a read mode to determine the resistive state of a memory plug, a first write mode to cause the memory plug to change from a first resistive state to a second resistive state, and a second write mode to cause the memory plug to change from the second resistive state back to the first resistive state.

Abstract: Line drivers that use minimal metal layers. Line driver connections typically need to be made to various other peripheral circuits. Although multiple metal layers could be used to make all the necessary connections, it is desirable to use the fewest metal layers possible. By keeping all y-direction lines on a first layer, and most of the x-direction lines on a second layer, only two metal layers are required. Additionally, an array cut could be used that allows line drivers to reach upper conductive array lines.

Abstract: A multilayered conductive memory device capable of storing information individually or as part of an array of memory devices is provided. Boundary control issues at the interface between layers of the device due to the use of incompatible materials can be avoided by intentionally doping the conductive metal oxide layers that are comprised of substantially similar materials. Methods of manufacture are also provided herein.

Abstract: Layouts of driver sets in a cross point memory array. Since both terminals of a memory cell in a cross point structure are typically used for selection purposes, dedicated driver sets are typically required for both x and y directions. By fabricating the cross point array above the driver circuitry, several different driver set layouts can be utilized that allow for varying designs.

Abstract: Providing a cross point memory array with memory plugs exhibiting a characteristic hysteresis. The memory plugs exhibit a hysteresis that, in the low resistive state, the first write threshold voltage is the point above which any voltages applied across the memory plug have substantially no effect on the resistive state and below which a voltage pulse will alter the resistance of the memory plug. Similarly, in the high resistive state, the second write threshold voltage is the point below which any voltages applied across the memory plug have substantially no effect on the resistive state and above which a voltage pulse will alter the resistance of the memory plug. The read voltages applied to the memory plug are typically above the first write threshold voltage and lower than the second write threshold voltage.

Abstract: Non-volatile memory cell with a single semiconductor device per memory cell. The present invention generally allows for a plurality of memory cells to be formed on a semiconductor substrate that supports a semiconductor device. A multi-resistive state material layer that changes its resistive state between a low resistive state and a high resistive state upon application of a voltage pulse is formed above the substrate, generally at a very high temperature. While the layers fabricated between the substrate and the multi-resistive state material use materials that can withstand high temperature processing, the layers fabricated above the multi-resistive state material do not need to withstand high temperature processing.

Abstract: Line drivers that fit within a specified line pitch. One method of placing line drivers completely underneath a cross point array requires splitting the line driver up so that a portion of the line drivers is on a first side of the cross point array and the other portion is on the opposite side. However, using this technique requires that the width of the drivers is no larger than the width of the memory cells that are being driven. This can be accomplished by stacking transistors such that line drivers fit within a specified line pitch, but are as long as is necessary to include all the necessary circuitry.

Abstract: Non-volatile memory cell with a single semiconductor device per memory cell. The present invention generally allows for a plurality of memory cells to be formed on a semiconductor substrate that supports a semiconductor device. A multi-resistive state material layer that changes its resistive state between a low resistive state and a high resistive state upon application of a voltage pulse is formed above the substrate, generally at a very high temperature. While the layers fabricated between the substrate and the multi-resistive state material use materials that can withstand high temperature processing, the layers fabricated above the multi-resistive state material do not need to withstand high temperature processing.

Abstract: A re-writable memory with multiple memory layers. Using both terminals of a memory cell in a stacked cross point structure for selection purposes allows multiple layers of conductive lines to be selected as long as there is only one memory cell that has two terminals selected. Sharing logic over multiple layers allows driver sets to be reused.

Abstract: A 2-terminal trapped charge memory device is disclosed with voltage switchable multi-level resistance. The trapped charge memory device has a trapped charge memory body sandwiched between two electrodes. The trapped charge memory body can be made of a variety of semiconducting or insulating materials of single-crystalline, poly-crystalline or amorphous structure while containing current carrier traps whose respective energy levels and degrees of carrier occupancy, modifiable by the height and width of an applied write voltage pulse, determine the resistance. The mechanism of modification can be through carrier tunneling, free carrier capturing, trap-hopping conduction or Frenkel-Poole conduction. The current carrier traps can be created with dopant varieties or an initialization procedure.

Abstract: Cross point memory array using multiple thin films. The invention is a cross point memory array that uses conductive array lines and multiple thin films as a memory plug. The thin films of the memory plug include a memory element and a non-ohmic device. The memory element switches between resistive states upon application of voltage pulses and the non-ohmic device imparts a relatively high resistance to the memory plug upon application of low magnitude voltages.

Abstract: A memory array contains memory cells designed to be erased using Fowler-Nordheim (“FN”) tunneling through the channel area, and programmed using either channel hot electron injection (“CHE”) or channel-initiated secondary electron injection (“CISEI”). To reduce disturbance of the floating gate potential of unselected memory cells during programming operations and read operations, the unselected word lines are brought to a negative potential rather than ground potential. To reduce disturbance of the floating gate potential of unselected memory cells during FN erase operations, the unselected word lines are brought to a positive potential rather than ground potential.

Abstract: A memory array contains memory cells designed to be erased using Fowler-Nordheim (“FN”) tunneling through the channel area, and programmed using either channel hot electron injection (“CHE”) or channel-initiated secondary electron injection (“CISEI”). To reduce disturbance of the floating gate potential of unselected memory cells during programming operations and read operations, the unselected word lines are brought to a negative potential rather than ground potential. To reduce disturbance of the floating gate potential of unselected memory cells during FN erase operations, the unselected word lines are brought to a positive potential rather than ground potential.

Abstract: A common source flash memory array providing multiple well contact structures distributed within the array without the need for separate well tap regions connected to dedicated channel lines. The contact locations between Vss metal common source lines and source bus regions are used to provide additional contacts between Vss metal lines and p+ well taps, all of the source bus regions and the p+ well tap regions being encompassed within a double-well configuration. Depending on the specific embodiment of the present invention, the n+ diffused source bus regions and the nearby p+ well tap may: (a) be separately tied to the Vss metal common source line through separate contact metals (e.g., tungsten plugs); (b) be butted against each other and tied to a common Vss metal source line through separate contact metals; (c) be butted against each other and tied to a common Vss metal source line through a common contact metal (e.g.

Abstract: A memory device, such as a flash EEPROM, has zero birds' beaks and vertically overlapping gates to facilitate high cell density in the EEPROM's core. During fabrication, a layer of field oxide is formed over the core. The active regions are exposed by etching through the layer of field oxide to form vertically walled cavities around the active regions. The tunnel oxide, floating gate, interpoly dielectric, and the control gate are formed within each cavity so that the floating gate overlaps the control gate along the vertical walls. As a result, capacitive coupling between the gates is maintained, yet the horizontal dimensions of the cell decrease. Similarly, the absence of birds' beaks facilitates higher cell density in the core.

Abstract: A memory device, such as a flash EEPROM, has zero birds' beaks and vertically overlapping gates to facilitate high cell density in the EEPROM's core. During fabrication, a layer of field oxide is formed over the core. The active regions are exposed by etching through the layer of field oxide to form vertically walled cavities around the active regions. The tunnel oxide, floating gate, interpoly dielectric, and the control gate are formed within each cavity so that the floating gate overlaps the control gate along the vertical walls. As a result, capacitive coupling between the gates is maintained, yet the horizontal dimensions of the cell decrease. Similarly, the absence of birds' beaks facilitates higher cell density in the core.