| Patent application number | Description | Published |
|---|
| 20080273379 | Programming a normally single phase chalcogenide material for use as a memory of FPLA - 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. | 11-06-2008 |
| 20090142927 | Fabricating sub-lithographic contacts - A small critical dimension element, such as a heater for an ovonic unified memory, may be formed within a pore by using successive sidewall spacers. The use of at least two successive spacers enables the limitations imposed by lithography and the limitations imposed by bread loafing to be overcome to provide reduced critical dimension elements. | 06-04-2009 |
| 20090159867 | Phase change memory with layered insulator - A phase change memory may be formed with an insulator made up of two different layers having significantly different thermal conductivities. Pores may be formed within the stack of insulating layers and the pores may be filled with heaters, chalcogenide layers, and electrodes in some embodiments. The use of the two different insulator layers enables embodiments where thermal losses may be reduced and an amorphous region may be maintained along the entire length of the phase change material layer. | 06-25-2009 |
| 20090244962 | Immunity of phase change material to disturb in the amorphous phase - Disturb from the reset to the set state may be reduced by creating an amorphous phase that is substantially free of crystal nuclei when programming the reset state in a phase change memory. In some embodiments, this can be achieved by using a current or a voltage to program that exceeds the threshold voltage of the phase change memory element, but does not exceed a safe current voltage which would cause a disturb. | 10-01-2009 |
| 20090244963 | Programming multilevel cell phase change memories - A multilevel phase change memory cell may have a plurality of intermediate levels between a set and a reset or a crystalline and amorphous states. These intermediate levels between set and reset may be differentiated not only by programming current, but also by different programming pulse widths. As a result, the intermediate states may be positioned, on the programming current versus programming pulse width curve, in regions of common resistance with a relatively large range of programming current. | 10-01-2009 |
| 20090244964 | Reducing temporal changes in phase change memories - A phase change memory in the reset state may be heated to reduce or eliminate electrical drift. | 10-01-2009 |
| 20090257275 | Seasoning phase change memories - A seasoned phase change memory has been subjected to a longer pulse to adjust resistance levels prior to use of the phase change memory. | 10-15-2009 |
| 20110070715 | MANUFACTURING A PHASE CHANGE MEMORY DEVICE HAVING A RING HEATER - A ring shaped heater surrounds a chalcogenide region along the length of a cylindrical solid phase portion thereof defining a change phase memory element. The chalcogenide region is formed in a sub-lithographic pore, so that a relatively compact structure is achieved. Furthermore, the ring contact between the heater and the cylindrical solid phase portion results in a more gradual transition of resistance versus programming current, enabling multilevel memories to be formed. | 03-24-2011 |
| 20110136315 | Multi-Level Phase Change Memory - A phase change memory may be formed which is amenable to multilevel programming. The phase change material may be formed with a lateral extent which does not exceed the lateral extent of an underlying heater. As a result, the possibility of current bypassing the amorphous phase change material in the reset state is reduced, reducing the programming current that is necessary to prevent this situation. In addition, a more controllable multilevel phase change memory may be formed in some embodiments. | 06-09-2011 |
| 20110155986 | DUAL RESISTANCE HEATER FOR PHASE CHANGE DEVICES AND MANUFACTURING METHOD THEREOF - A dual resistance heater for a phase change material region is formed by depositing a resistive material. The heater material is then exposed to an implantation or plasma which increases the resistance of the surface of the heater material relative to the remainder of the heater material. As a result, the portion of the heater material approximate to the phase change material region is a highly effective heater because of its high resistance, but the bulk of the heater material is not as resistive and, thus, does not increase the voltage drop and the current usage of the device. | 06-30-2011 |
