The disclosure relates to a phase change thermal storage ceramic having high service temperature and improved utilization rate and utilization efficiency of heat. It is prepared at a low cost with a simple, easy-to-industrially-realized method. A mixture is obtained by mixing and stirring evenly 50-85 wt % of fused mullite powder, 10-45 wt % of pretreated aluminum-silicon alloy powder, and 3-8 wt % of ball clay. A ceramic body is formed by press molding the mixture at 80-150 MPa. The ceramic body is cured at 25-28° C. and a relative humidity of 70-75 RH for 24-36 h, dried at 80-120° C. for 24-36 h, and held at 1,100-1,300° C. for 3-5 h to prepare the phase change thermal storage ceramic. The pretreated aluminum-silicon alloy powder is prepared by holding aluminum-silicon alloy powder in water vapor at 0.02-0.20 MPa for 0.5-3 h to impregnate in an alkaline silica sol and drying the impregnated powder.

The disclosed technology generally relates to a memory selector and to a memory device including the memory selector, and more particularly to the memory selector and the memory device implemented in a crossbar memory architecture. In one aspect, a memory selector for a crossbar memory architecture comprises a metal bottom electrode, a metal top electrode and an intermediate layer stack between and in contact with the metal top and bottom electrodes. A bottom Schottky barrier having a bottom Schottky barrier height (Φ.sub.B) is formed at the interface between the metal bottom electrode and the intermediate layer stack. A top Schottky barrier having a top Schottky barrier height (Φ.sub.T) is formed at the interface between the metal top electrode and the intermediate layer stack. The disclosed technology further relates to a random access memory (RAM) and a memory cell including the memory selector.

The present disclosure provides a memory structure, including a first interlayer dielectric layer (ILD), a second ILD over the first ILD, wherein at least a portion of an interconnect structure is in the second ILD, a first switch between the first ILD and the second ILD, a second switch over the first switch, and a first phase change material stacking with the first switch and the second switch.

A memory cell can include a top lamina layer, a bottom lamina layer, and a phase change material (PCM) layer between the top lamina layer and the bottom lamina layer. The PCM layer can have a top surface in direct contact with the top lamina layer and a bottom surface in direct contact with the bottom lamina layer. The top surface of the PCM layer and the bottom surface of the PCM layer can have a structurally stabilizing width ratio.

Methods, systems, and devices for memory cell selection to enable a memory device to select a targeted memory cell during a write operation are described. The memory device may apply a first pulse to a selected bit line of the targeted memory cell while applying a voltage to deselected word lines to prevent current leakage. If the targeted memory is not selected after the first pulse, the memory device may apply a second pulse to the selected bit line while applying a voltage to the deselected word lines. If the targeted memory cell is not selected following the second pulse, the memory device may apply a third pulse to the selected bit line while applying the voltage to the deselected word lines. The memory device may detect a snapback event after any of the pulses if the targeted memory cell is selected.

According to one embodiment, a semiconductor memory device includes a plurality of first interconnects extending in a first direction, a plurality of second interconnects extending in a second direction, a plurality of stacked films respectively provided between the first interconnects and the second interconnects, each of the plurality of stacked films including a variable resistance film, a first inter-layer insulating film provided in a first region between the stacked films, and a second inter-layer insulating film provided in a second region having a wider width than the first region. The second inter-layer insulating film includes a plurality of protrusions configured to support one portion of the plurality of second interconnects on the second region. A protruding length of the protrusions is less than a stacking height of the stacked films.

According to some embodiments of the present invention a phase change device (PCD) has a first and second semiconductor layer. The first semiconductor layer made of a first semiconductor material and has a first semiconductor thickness, a first interface surface, and a first electrode surface. The first interface surface and first electrode surface are on opposite sides of the first semiconductor layer. The first semiconductor material can transition between a first amorphous state and a first crystalline state at one or more first conditions. The second semiconductor layer is made of a second semiconductor material and has a second semiconductor thickness, a second interface surface, and a second electrode surface. The second interface surface and second electrode surface are on opposite sides of the second semiconductor layer. The first interface surface and the second interface surface are in electrical, physical, and chemical contact with one another at an interface. The second semiconductor material can transition between a second amorphous state and a second crystalline state at one or more second conditions. A first electrode in physical and electrical contact with the first electrode surface of the first semiconductor layer and a second electrode in physical and electrical contact with the second electrode surface of the second semiconductor layer. The first conditions and second conditions are different. Therefore, in some embodiments, the first and second semiconductor materials can be in different amorphous and/or crystalline states. The layers can have split amorphous/crystalline states. By controlling how the layers are split, the PCD can be in different resistive states.

Methods, systems, and devices for programming enhancement in memory cells are described. An asymmetrically shaped memory cell may enhance ion crowding at or near a particular electrode, which may be leveraged for accurately reading a stored value of the memory cell. Programming the memory cell may cause elements within the cell to separate, resulting in ion migration towards a particular electrode. The migration may depend on the polarity of the cell and may create a high resistivity region and low resistivity region within the cell. The memory cell may be sensed by applying a voltage across the cell. The resulting current may then encounter the high resistivity region and low resistivity region, and the orientation of the regions may be representative of a first or a second logic state of the cell.

A non-volatile memory structure may include a phase change memory comprising a phase change material. The non-volatile memory structure may include a Schottky diode in series with the phase change memory, wherein a Schottky barrier of the Schottky diode is a surface of the phase change memory. This may be accomplished through a proper selection of materials for the contact of the phase change memory. This may create an integrated diode-memory structure which may control directionality of current without a penalty on the footprint of the structure.

Embodiments include a threshold switching selector. The threshold switching selector may include a threshold switching layer and a semiconductor layer between two electrodes. A memory cell may include the threshold switching selector coupled to a storage cell. The storage cell may be a PCRAM storage cell, a MRAM storage cell, or a RRAM storage cell. In addition, a RRAM device may include a RRAM storage cell, coupled to a threshold switching selector, where the threshold switching selector may include a threshold switching layer and a semiconductor layer, and the semiconductor layer of the threshold switching selector may be shared with the semiconductor layer of the RRAM storage cell.