Patent application number | Description | Published |
20100328995 | METHODS AND APPARATUS FOR REDUCING DEFECT BITS IN PHASE CHANGE MEMORY - Phase change memory devices and methods for operating described herein are based on the discovery that, following an initial high current operation applied to a phase change memory cell to establish the high resistance reset state, the current-voltage (I-V) behavior of the memory cell under different bias voltages can be used to detect if the memory cell is a defect cell having poor data retention characteristics. | 12-30-2010 |
20110069538 | MULTI-LEVEL CELL PROGRAMMING OF PCM BY VARYING THE RESET AMPLITUDE - A phase change memory device and a method for programming the same. The method includes determining a characterized lowest SET current and corresponding SET resistance for the phase change memory device. The method includes determining a characterized RESET current slope for the phase change memory device. The method also includes calculating a first current amplitude for a RESET pulse based on the characterized lowest SET current and the characterized RESET current slope. The method includes applying the RESET pulse to a target memory cell in the phase change memory device and measuring the resistance of the target memory cell. If the measured resistance is substantially less than a target resistance, the method further includes applying one or more additional RESET pulses. In one embodiment of the invention, the one or more additional RESET pulses have current amplitudes greater than a previously applied RESET pulse. | 03-24-2011 |
20120018845 | Polysilicon Plug Bipolar Transistor For Phase Change Memory - Memory devices and methods for manufacturing are described herein. A memory device described herein includes a plurality of memory cells. Memory cells in the plurality of memory cells comprise respective bipolar junction transistors and memory elements. The bipolar junction transistors are arranged in a common collector configuration and include an emitter comprising doped polysilicon having a first conductivity type, the emitter contacting a corresponding word line in a plurality of word lines to define a pn junction. The bipolar junction transistors include a portion of the corresponding word line underlying the emitter acting as a base, and a collector comprising a portion of the single-crystalline substrate underlying the base. | 01-26-2012 |
20120120701 | TERNARY CONTENT ADDRESSABLE MEMORY USING PHASE CHANGE DEVICES - A content addressable memory device with a plurality of memory cells storing ternary data values of high, low, and don't care. An aspect of the content addressable memory device is the use of first memory elements and second memory elements in the memory cells. The first and second memory elements are electrically coupled in parallel circuit to a match-line. The first memory elements are coupled to first word-lines and the second memory elements are coupled to second word-lines. The first memory elements are configured to store low resistance states if the ternary data value is low and high resistance states if the ternary data value is either high or don't care. The second memory elements are configured to store the low resistance states if the ternary data value is high and the high resistance states if the ternary data value is either low or don't care. | 05-17-2012 |
20120140554 | COMPACT LOW-POWER ASYNCHRONOUS RESISTOR-BASED MEMORY READ OPERATION AND CIRCUIT - A compact, low-power, asynchronous, resistor-based memory read circuit includes a memory cell having a plurality of consecutive memory states, each of said states corresponding to a respective output voltage. A sense amplifier reads the state of the memory cell. The sense amplifier includes a voltage divider configured to receive the output voltage of the memory cell and to output a settled voltage an amplifier having a voltage threshold between the settled voltages associated with two of said consecutive memory states, configured to discriminate between said two consecutive memory states. | 06-07-2012 |
20120147666 | PHASE CHANGE MATERIAL CELL WITH STRESS INDUCER LINER - An example embodiment disclosed is a phase change memory cell. The memory cell includes a phase change material and a transducer positioned proximate the phase change material. The phase change material is switchable between at least an amorphous state and a crystalline state. The transducer is configured to activate when the phase change material is changed from the amorphous state to the crystalline state. In a particular embodiment, the transducer is ferroelectric material. | 06-14-2012 |
20130026436 | PHASE CHANGE MEMORY ELECTRODE WITH SHEATH FOR REDUCED PROGRAMMING CURRENT - An example embodiment is a phase change memory cell that includes a bottom contact and an electrically insulating layer disposed over the bottom contact. The electrically insulating layer defines an elongated via. Furthermore, a bottom electrode is disposed at least partially in the via. The bottom electrode includes a sleeve of a first electrically conductive material surrounding a rod of a second electrically conductive material. The first electrically conductive material and the second electrically conductive material have different specific electrical resistances. The memory cell also includes a phase change layer electrically coupled to the first electrode. | 01-31-2013 |
20130173515 | ELECTRONIC SYNAPSES FROM STOCHASTIC BINARY MEMORY DEVICES - According to a technique, an electronic device is configured to correspond to characteristic features of a biological synapse. The electronic device includes multiple bipolar resistors arranged in parallel to form an electronic synapse, an axonal connection connected to one end of the electronic synapse and to a first electronic neuron, and a dendritic connection connected to another end of the electronic synapse and to a second electronic neuron. An increase and decrease of synaptic conduction in the electronic synapse is based on a probability of switching the plurality of bipolar resistors between a low resistance state and a high resistance state. | 07-04-2013 |
20130173516 | ELECTRONIC SYNAPSES FROM STOCHASTIC BINARY MEMORY DEVICES - According to a technique, an electronic device is configured to correspond to characteristic features of a biological synapse. The electronic device includes multiple bipolar resistors arranged in parallel to form an electronic synapse, an axonal connection connected to one end of the electronic synapse and to a first electronic neuron, and a dendritic connection connected to another end of the electronic synapse and to a second electronic neuron. An increase and decrease of synaptic conduction in the electronic synapse is based on a probability of switching the plurality of bipolar resistors between a low resistance state and a high resistance state. | 07-04-2013 |
20130299768 | THERMALLY INSULATED PHASE CHANGE MATERIAL CELLS - Memory cell structures for phase change memory. An example memory cell structure comprising includes a bottom electrode comprised of electrically conducting material, and phase change material disposed above the bottom electrode. A layer of thermally insulating material is disposed, at least partially, between the bottom electrode and the phase change material. The thermally insulating material is comprised of Tantalum Oxide. A top electrode is comprised of electrically conducting material. | 11-14-2013 |
20130309782 | PHASE CHANGE MATERIAL CELL WITH PIEZOELECTRIC OR FERROELECTRIC STRESS INDUCER LINER - An example embodiment disclosed is a process for fabricating a phase change memory cell. The method includes forming a bottom electrode, creating a pore in an insulating layer above the bottom electrode, depositing piezoelectric material in the pore, depositing phase change material in the pore proximate the piezoelectric material, and forming a top electrode over the phase change material. Depositing the piezoelectric material in the pore may include conforming the piezoelectric material to at least one wall defining the pore such that the piezoelectric material is deposited between the phase change material and the wall. The conformal deposition may be achieved by chemical vapor deposition (CVD) or by atomic layer deposition (ALD). | 11-21-2013 |
20140078837 | COMPACT LOW-POWER ASYNCHRONOUS RESISTOR-BASED MEMORY READ OPERATION AND CIRCUIT - A compact, low-power, asynchronous, resistor-based memory read circuit includes a memory cell having a plurality of consecutive memory states, each of said states corresponding to a respective output voltage. A sense amplifier reads the state of the memory cell. The sense amplifier includes a voltage divider configured to receive the output voltage of the memory cell and to output a settled voltage an amplifier having a voltage threshold between the settled voltages associated with two of said consecutive memory states, configured to discriminate between said two consecutive memory states. | 03-20-2014 |
20140241048 | PHASE CHANGE MEMORY MANAGEMENT - A three dimensional (3D) stack of phase change memory (PCM) devices which includes PCM devices stacked in a 3D array, the PCM devices having memory regions; a memory management unit on at least one of the PCM devices; a stack controller in the memory management unit to monitor an ambient device temperature (T | 08-28-2014 |