Abstract: The present invention relates to a process of forming a phase-change memory. A lower electrode is disposed in a first dielectric film. The lower electrode comprises an upper section and a lower section. The upper section extends beyond the first dielectric film. Resistivity in the upper section is higher than in the lower section. A second dielectric film is disposed over the first dielectric film and has an upper surface that is coplanar with the upper section at an upper surface.

Abstract: The memory device has constituent cells which include a structural phase-change material to store the cells data. This material may be, for instance, a chalcogenide alloy. A first pulse is applied to the cell to leave the material in a first state, such as a reset state in which the material is relatively amorphous and has relatively high resistivity. Thereafter, a second pulse is applied to the cell to change the material from the first state to a second, different state, such as a set state in which the material is relatively crystalline and has relatively low resistivity. This second pulse has a generally triangular shape, rather than a rectangular one.

Abstract: An electronic semiconductor device has a sublithographic contact area between a first conductive region and a second conductive region. The first conductive region is cup-shaped and has vertical walls which extend, in top plan view, along a closed line of elongated shape. One of the walls of the first conductive region forms a first thin portion and has a first dimension in a first direction. The second conductive region has a second thin portion having a second sublithographic dimension in a second direction transverse to the first dimension. The first and the second conductive regions are in direct electrical contact at their thin portions and form the sublithographic contact area. The elongated shape is chosen between rectangular and oval elongated in the first direction. Thereby, the dimensions of the contact area remain approximately constant even in presence of a small misalignment between the masks defining the conductive regions.

Abstract: A method comprising forming a sacrificial layer over less than the entire portion of a contact area on a substrate, the sacrificial layer having a thickness defining an edge over the contact area, forming a spacer layer over the spacer, the spacer layer conforming to the shape of the first sacrificial layer such that the spacer layer comprises an edge portion over the contact area adjacent the first sacrificial layer edge, removing the sacrificial layer, while retaining the edge portion of the spacer layer over the contact area, forming a dielectric layer over the contact area, removing the edge portion, and forming a programmable material to the contact area formerly occupied by the edge portion.

Abstract: Briefly, in accordance with an embodiment of the invention, a method and an apparatus to read a phase change memory is provided, wherein the method includes zero biasing unselected memory cells during reading of a selected memory cell.

Abstract: The phase change memory cell is formed by a resistive element and by a memory region of a phase change material. The resistive element has a first thin portion having a first sublithographic dimension in a first direction; and the memory region has a second thin portion having a second sublithographic dimension in a second direction transverse to the first dimension. The first thin portion and the second thin portion are in direct electrical contact and define a contact area of sublithographic extension. The second thin portion is delimited laterally by oxide spacer portions surrounded by a mold layer which defines a lithographic opening. The spacer portions are formed after forming the lithographic opening, by a spacer formation technique.

Abstract: A nonvolatile memory device is described comprising a memory array, a row decoder and a column selector for addressing the memory cells of the memory array, and a biasing stage for biasing the array access device terminal of the addressed memory cell. The biasing stage is arranged between the column selector and the memory array and comprises a biasing transistor having a drain terminal connected to the column selector, a source terminal connected to the array access device terminal of the addressed memory cell, and a gate terminal receiving a logic driving signal, the logic levels of which are defined by precise and stable voltages and are generated by a logic block and an output buffer cascaded together. The output buffer may be supplied with either a read voltage or a program voltage supplied by a multiplexer.

Abstract: A contact structure, including a first conducting region having a first thin portion with a first sublithographic dimension in a first direction; a second conducting region having a second thin portion with a second sublithographic dimension in a second direction transverse to said first direction; the first and second thin portions being in direct electrical contact and defining a contact area having a sublithographic extension. The thin portions are obtained using deposition instead of lithography: the first thin portion is deposed on a wall of an opening in a first dielectric layer; the second thin portion is obtained by deposing a sacrificial region on vertical wall of a first delimitation layer, deposing a second delimitation layer on the free side of the sacrificial region, removing the sacrificial region to form a sublithographic opening that is used to etch a mold opening in a mold layer and filling the mold opening.

Abstract: The phase change memory cell is formed by a resistive element and by a memory region of a phase change material. The resistive element has a first thin portion having a first sublithographic dimension in a first direction; and the memory region has a second thin portion having a second sublithographic dimension in a second direction which is transverse to said first direction. The first and second thin portions are in direct electrical contact and define a contact area having sublithographic extent. The second thin portion is formed in a slit of sublithographic dimensions. According to a first solution, oxide spacer portions are formed in a lithographic opening, delimited by a mold layer. According to a different solution, a sacrificial region is formed on top of a mold layer and is used for forming the sublithographic slit in the mold layer.

Abstract: The invention relates to a phase-change memory device. The device includes a double-wide trench into which a single film is deposited but two isolated lower electrodes are formed therefrom. Additionally a diode stack is formed that communicates to the lower electrode. Additionally, other isolated lower electrodes may be formed along a symmetry line that is orthogonal to the first two isolated lower electrodes. The present invention also relates to a method of making a phase-change memory device. The method includes forming two orthogonal and intersecting isolation structure s around a memory cell structure diode stack.

Abstract: The phase-change nonvolatile memory array is formed by a plurality of memory cells extending in a first and in a second direction orthogonal to each other. A plurality of column-selection lines extend parallel to the first direction. A plurality of word-selection lines extend parallel to the second direction. Each memory cell includes a PCM storage element and a selection transistor. A first terminal of the selection transistor is connected to a first terminal of the PCM storage element, and the control terminal of the selection transistor is connected to a respective word-selection line. A second terminal of the PCM storage element is connected to a respective column-selection line, and a second terminal of the selection transistor is connected to a reference-potential region while reading and programming the memory cells.

Abstract: An apparatus including a contact on a substrate, a dielectric material overlying the contact, a phase change element overlying the dielectric material on a substrate, and a heater element disposed in the dielectric material and coupled to the contact and the phase change element, wherein a portion of the dielectric material comprises a thermal conductivity less than silicon dioxide. A method including introducing over a contact formed on a substrate, a dielectric material, a portion of which comprises a thermal conductivity less than silicon dioxide, introducing a heater element through the dielectric material to the contact, and introducing a phase change material over the dielectric material and the heater element.

Abstract: An electrically operated memory element having a contact in electrical communication with a memory material programmable to at least a first resistance state and a second resistance state. Preferably, the contact includes at least a first region having a first resistivity and a second region having a second resistivity greater than the first resistivity where the more resistive region is adjacent to the memory material.

Abstract: A method for making a small pore. The defined pore is useful for the fabrication of programmable resistance memory elements. The programmable resistance memory material may be a chalcogenide.

Abstract: A memory system, comprising: a memory cell comprising a programmable resistance element programmable to at least a first resistance state and a second resistance state. The memory cell interconnecting a row line and a column line. A power line, distinct from the row line and the column line, coupling said memory cell to a power source.

Abstract: The invention relates to a process of forming a phase-change memory device. The process includes forming a salicide structure in peripheral logic portion of the substrate and preventing forming salicide structures in the memory array. The device may include a double-wide trench into which a single film is deposited but two isolated lower electrodes are formed therefrom. Additionally a diode stack is formed that communicates to the lower electrode.

Abstract: A method of making a electrically operated programmable resistance memory element. A silylated photoresist sidewall spacer is used as a mask for form raised portions on an edge of a conductive layer. The modified conductive layer is used as an electrode for the memory element.

Abstract: The memory device has constituent cells which include a structural phase-change material to store the cells data. This material may be, for instance, a chalcogenide alloy. A first pulse is applied to the cell to leave the material in a first state, such as a reset state in which the material is relatively amorphous and has relatively high resistivity. Thereafter, a second pulse is applied to the cell to change the material from the first state to a second, different state, such as a set state in which the material is relatively crystalline and has relatively low resistivity. This second pulse has a generally triangular shape, rather than a rectangular one.

Abstract: An apparatus including a volume of phase change material disposed between a first conductor and a second conductor on a substrate, and a plurality of electrodes coupled to the volume of phase change material and the first conductor. A method including introducing, over a first conductor on a substrate, a plurality of electrodes coupled to the first conductor, introducing a phase change material over the plurality of electrodes and in electrical communication with the plurality of electrodes, and introducing a second conductor over the phase change material and coupled to the phase change material.

Abstract: A memory device including a plurality of memory cells, a plurality of insulated first regions of a first type of conductivity formed in a chip of semiconductor material, at least one second region of a second type of conductivity formed in each first region, a junction between each second region and the corresponding first region defining a unidirectional conduction access element for selecting a corresponding memory cell connected to the second region when forward biased, and at least one contact for contacting each first region; a plurality of access elements are formed in each first region, the access elements being grouped into at least one sub-set consisting of a plurality of adjacent access elements without interposition of any contact, and the memory device further includes means for forward biasing the access elements of each sub-set simultaneously.