Abstract: The present invention relates to a semiconductor structure and its forming method, and a memory and its forming method. The semiconductor structure includes a substrate, a vertical transistor on the substrate, and a bit line connected to the bottom of the vertical transistor and disposed between the bottom of the vertical transistor and the substrate. The vertical transistor in such a semiconductor structure has a relatively small plane dimension.

Abstract: Some embodiments include apparatuses and methods of forming the apparatuses. One of the apparatuses includes a memory cell and first, second, and third data lines located over a substrate. The memory cell includes a first transistor and a second transistor. The first transistor includes a charge storage structure located on a first level of the apparatus, and a first channel region electrically separated from the charge storage structure. The second transistor includes a second channel region located on a second level of the apparatus and electrically coupled to the charge storage structure. The first and second data lines are located on a third level of the apparatus and electrically coupled to the first channel region. The first level is between the substrate and the third level. The third data line is electrically coupled to the second channel region and electrically separated from the first channel region.

Abstract: An analog error correction circuit is disclosed that implements an analog error correction code. The analog circuit includes a crossbar array of memristors or other non-volatile tunable resistive memory devices. The crossbar array includes a first crossbar array portion programmed with values of a target computation matrix and a second crossbar array portion programmed with values of an encoder matrix for correcting computation errors in the matrix multiplication of an input vector with the computation matrix. The first and second crossbar array portions share the same row lines and are connected to a third crossbar array portion that is programmed with values of a decoder matrix, thereby enabling single-cycle error detection. A computation error is detected based on output of the decoder matrix circuitry and a location of the error is determined via an inverse matrix multiplication operation whereby the decoder matrix output is fed back to the decoder matrix.

Abstract: A semiconductor memory device, includes: a stack including a wiring layer and an insulation layer alternately stacked in a first direction; a semiconductor layer including a first region overlapping with the insulation layer in a second direction, and a second region overlapping with the wiring layer in the second direction; an insulation region between the wiring layer and the second region; and a memory region on the opposite side of the second region from the wiring layer. The wiring layer is farther from the first region in the second direction than the insulation layer is. The second region has a part between the insulation layers in the first direction and protruding further toward the wiring layer than the first region in the second direction. The memory region has a face opposite to the second region and closer to the wiring layer in the second direction than the first region is.

Abstract: A staggered memory cell architecture staggers memory cells on opposite sides of a shared bit line preserves memory cell density, while increasing the distance between such memory cells, thereby reducing the possibility of a disturb. In one implementation, the memory cells along a first side of a shared bit line are connected to a set of global word lines provided underneath the memory structure, while the memory cells on the other side of the shared bit line—which are staggered relative to the memory cells on the first side—are connected to global word lines above the memory structure.

Abstract: Electronic devices comprising a doped dielectric material adjacent to a source contact, tiers of alternating conductive materials and dielectric materials adjacent to the doped dielectric material, and pillars extending through the tiers, the doped dielectric material, and the source contact and into the source stack. Related methods and electronic systems are also disclosed.

Abstract: A transistor comprises a lower contact structure, a channel structure, a dielectric fill structure, and an upper contact structure. The lower contact structure comprises a first oxide semiconductive material. The channel structure contacts the lower contact structure and comprises a second oxide semiconductive material having a smaller atomic concentration of one or more metals than the first oxide semiconductive material. The dielectric fill structure contacts an inner side surface of the channel structure and has a recessed upper surface relative to the channel structure. The upper contact structure comprises a third oxide semiconductive material having a greater atomic concentration of the one or more metals than the channel structure. The upper contact structure comprises a first portion contacting the upper surface of the dielectric fill structure and the inner side surface of the channel structure, and a second portion contacting the upper surface of the channel structure.

Abstract: A method includes: generating a first difference between a first resistance value of a first memory cell and a first predetermined resistance value; generating a first signal based on the first difference; applying the first signal to the first memory cell to adjust the first resistance value; and after the first signal is applied to the first memory cell, comparing the first resistance value and the first predetermined resistance value, to further adjust the first resistance value until the first resistance value reaches the first predetermined resistance value. A memory device is also disclosed herein.

Abstract: A semiconductor device, the device including: a first level including a plurality of first memory arrays, where the first level includes a plurality of first transistors and a plurality of metal layers; a second level disposed on top of the first level, where the second level includes a plurality of second memory arrays, where the first level is bonded to the second level, where the bonded includes oxide to oxide bonding regions and a plurality of metal to metal bonding regions, where the plurality of first memory arrays includes a plurality of first DRAM (Dynamic Random Access Memory) cells, and where the plurality of second memory arrays includes a plurality of second DRAM (Dynamic Random Access Memory) cells.

Abstract: An analog error correction circuit is disclosed that implements an analog error correction code. The analog circuit includes a crossbar array of memristors or other non-volatile tunable resistive memory devices. The crossbar array includes a first crossbar array portion programmed with values of a target computation matrix and a second crossbar array portion programmed with values of an encoder matrix for correcting computation errors in the matrix multiplication of an input vector with the computation matrix. The first and second crossbar array portions share the same row lines and are connected to a third crossbar array portion that is programmed with values of a decoder matrix, thereby enabling single-cycle error detection. A computation error is detected based on output of the decoder matrix circuitry and a location of the error is determined via an inverse matrix multiplication operation whereby the decoder matrix output is fed back to the decoder matrix.

Abstract: Electrically formed memory arrays, and methods of processing the same are described herein. A number of embodiments include a plurality of conductive lines separated from one other by an insulation material, a first plurality of conductive extensions arranged to extend substantially perpendicular to the plurality of conductive lines, a storage element material formed around each respective one of the first plurality of conductive extensions, a second plurality of conductive extensions arranged to extend substantially perpendicular to the plurality of conductive lines, and a plurality of single element materials formed around each respective one of the second plurality of conductive extensions.

Abstract: A multi-bit resistive random access memory cell includes a plurality of bottom electrodes, a plurality of dielectric layers, a top electrode and a resistance layer. The bottom electrodes and the dielectric layers are interleaved layers, each of the bottom electrodes is sandwiched by the dielectric layers, and a through hole penetrates through the interleaved layers. The top electrode is disposed in the through hole. The resistance layer is disposed on a sidewall of the through hole and is between the top electrode and the interleaved layers, thereby the top electrode, the resistance layer and the bottom electrodes constituting a multi-bit resistive random access memory cell. The present invention also provides a method of forming the multi-bit resistive random access memory cell.

Abstract: Some embodiments include an arrangement having a memory tier with memory cells on opposing sides of a coupling region. First sense/access lines are under the memory cells, and are electrically connected with the memory cells. A conductive interconnect is within the coupling region. A second sense/access line extends across the memory cells, and across the conductive interconnect. The second sense/access line has a first region having a second conductive material over a first conductive material, and has a second region having only the second conductive material. The first region is over the memory cells, and is electrically connected with the memory cells. The second region is over the conductive interconnect and is electrically coupled with the conductive interconnect. An additional tier is under the memory tier, and includes CMOS circuitry coupled with the conductive interconnect. Some embodiments include methods of forming multitier arrangements.

Abstract: The present disclosure includes three dimensional memory arrays, and methods of processing the same. A number of embodiments include a plurality of conductive lines separated from one other by an insulation material, a plurality of conductive extensions arranged to extend substantially perpendicular to the plurality of conductive lines, and a storage element material formed around each respective one of the plurality of conductive extensions and having two different contacts with each respective one of the plurality of conductive lines, wherein the two different contacts with each respective one of the plurality of conductive lines are at two different ends of that respective conductive line.

Abstract: A semiconductor device includes a transistor, a bit line and a bit-line via structure. The transistor is located in a transistor layer, and has a source contact and a drain contact. The bit line is electrically connected to one of the source contact and the drain contact. The bit-line via structure is located in the transistor layer, and electrically interconnects the bit line and a periphery device.

Abstract: An example three-dimensional (3-D) memory array includes a first plurality of conductive lines separated from one other by an insulation material, a second plurality of conductive lines, and a plurality of pairs of conductive pillars arranged to extend substantially perpendicular to the first plurality of conductive lines and the second plurality of conductive lines. The conductive pillars of each respective pair are coupled to a same conductive line of the second plurality of conductive lines. A storage element material is formed partially around the conductive pillars of each respective pair.

Abstract: Methods, systems, and devices for memory arrays having graded memory stack resistances are described. An apparatus may include a first subset of memory stacks having a first resistance based on a physical and/or electrical distance of the first subset of memory stacks from at least one of a first driver component or a second driver component. The apparatus may include a second subset of memory stacks having a second resistance that is less than the first resistance based on a physical and/or electrical distance of the second subset of memory from at least one of the first driver component or the second driver component.

Abstract: A staggered memory cell architecture staggers memory cells on opposite sides of a shared bit line preserves memory cell density, while increasing the distance between such memory cells, thereby reducing the possibility of a disturb. In one implementation, the memory cells along a first side of a shared bit line are connected to a set of global word lines provided underneath the memory structure, while the memory cells on the other side of the shared bit line—which are staggered relative to the memory cells on the first side—are connected to global word lines above the memory structure.

Abstract: A memory device is disclosed. The memory device includes a bottom contact, and a memory layer connected to the bottom contact, where the memory layer has a variable resistance. The memory device also includes a top electrode on the memory layer, where the top electrode and the memory layer cooperatively form a heterojunction memory structure. The memory device also includes a top contact on the top electrode, and a first barrier layer, including a first oxide material and a second oxide material, where the first oxide material is different from the second oxide material, and where the first barrier layer is between one of A) the memory layer and the bottom contact, and B) the top electrode and the top contact, where the first barrier layer is configured to substantially prevent the conduction of ions or vacancies therethrough.

Abstract: Methods and apparatuses for thin film transistors and related fabrication techniques are described. The thin film transistors may access two or more decks of memory cells disposed in a cross-point architecture. The fabrication techniques may use one or more patterns of vias formed at a top layer of a composite stack, which may facilitate building the thin film transistors within the composite stack while using a reduced number of processing steps. Different configurations of the thin film transistors may be built using the fabrication techniques by utilizing different groups of the vias. Further, circuits and components of a memory device (e.g., decoder circuitry, interconnects between aspects of one or more memory arrays) may be constructed using the thin film transistors as described herein along with related via-based fabrication techniques.

Abstract: A three-dimensional memory device includes an alternating stack of insulating layers and electrically conductive word line layers located over a substrate, and a plurality of vertical memory strings. Each vertical memory string includes a series connection of a memory stack structure and a selector element. Each of the memory stack structures extends through the alternating stack and includes a respective memory film and a respective vertical semiconductor channel. Each of the selector elements includes a two terminal device that is configured to provide at least two different resistivity states.

Abstract: A wavelength multiplexing device is disclosed. When light is irradiated on a first longitudinal end region of a metal nano-structure, surface plasmon polaritons are generated in the first longitudinal end region. The surface plasmon polaritons and the light are coupled with each other to form first coupled surface plasmon polaritons, wherein the first coupled surface plasmon polaritons propagate along and on a surface of the metal nano-structure. When the first coupled surface plasmon polaritons reach a two-dimensional material layer, excitons are induced in the two-dimensional material layer, wherein the induced excitons and the first coupled surface plasmon polaritons are coupled with each other to form second coupled surface plasmon polaritons. The second coupled surface plasmon polaritons propagate along and on a surface of the metal nano-structure toward a second longitudinal end thereof.

Abstract: Methods, systems, and devices for techniques for forming self-aligned memory structures are described. Aspects include etching a layered assembly of materials including a first conductive material and a first sacrificial material to form a first set of channels along a first direction that creates a first set of sections. An insulative material may be deposited within each of the first set of channels and a second sacrificial material may be deposited onto the first set of sections and the insulating material. A second set of channels may be etched into the layered assembly of materials along a second direction that creates a second set of sections, where the second set of channels extend through the first and second sacrificial materials. Insulating material may be deposited in the second set of channels and the sacrificial materials removed leaving a cavity. A memory material may be deposited in the cavity.

Abstract: A semiconductor device includes a substrate, a stack, a conductive pillar, a memory layer, and a salicide layer. The stack is disposed on the substrate, wherein the stack includes a plurality of insulating layers and a plurality of conductive layers that are alternately stacked along a first direction. The conductive pillar penetrates the stack along the first direction. The memory layer surrounds the conductive pillar. The salicide layer surrounds the conductive pillar, wherein the memory layer is disposed between the conductive pillar and the salicide layer.

Abstract: Disclosed herein are selector devices and related devices and techniques. In some embodiments, a selector device may include a first electrode, a second electrode, and a selector material between the first electrode and the second electrode. The selector material may include germanium, tellurium, and sulfur.

Abstract: A nonvolatile memory device according to an embodiment includes a substrate having an upper surface, a source electrode structure disposed on the substrate, and a channel structure disposed over the substrate and disposed to contact one sidewall surface of the source electrode structure. In addition, the nonvolatile memory device includes a drain electrode structure disposed to contact one sidewall surface of the channel structure over the substrate. In addition, the nonvolatile memory device includes a plurality of ferroelectric structures extending in a first direction perpendicular to the substrate in the channel structure and disposed to be spaced apart from each other along the second direction perpendicular to the first direction. In addition, the nonvolatile memory device includes a gate electrode structure disposed in each of the plurality of ferroelectric structure to extend along the first direction.

Abstract: Technologies relating to crossbar array circuits with proton-based two-terminal volatile memristive devices are disclosed. An example apparatus includes: a first bottom conductive layer, a first switching oxide layer formed on the first bottom conductive layer, a first top conductive layer formed on the first switching oxide layer, an intermediate layer formed on the first top conductive layer, a second bottom conductive layer formed on the intermediate layer, a second oxide layer whose conductance can be modulated by H-dopant formed on the second bottom conductive layer; and a proton reservoir layer formed on the second oxide layer, wherein the second bottom conductive layer is H-doped.

Abstract: A memory cell can include a chalcogenide material configured in an annular shape or a chalcogenide material substantially circumscribing an interior conductive channel. Such memory cells can be included in memory structures having an interior conductive channel and a plurality of alternating dielectric layers and memory layers oriented along the interior conductive channel. Individual memory layers can include a chalcogenide material substantially circumscribing the interior conductive channel.

Abstract: A method for forming a semiconductor device is provided. In the disclosed method, a stack is formed on a working surface of a substrate. The stack has alternating first layers and second layers positioned over the substrate. A separation structure is formed in the stack that separates the stack into a first region and a second region, where the separation structure extends in a first direction of the substrate. The second layers in the second region are further replaced with insulating layers, and the first layers in the second region are doped with a dopant.

Abstract: Vertical memory devices and method of manufacturing the same are disclosed. The vertical memory device includes a substrate having a cell block area, a block separation area and a boundary area, a plurality of stack structures arranged in the cell block area and the boundary area such that insulation interlayer patterns are stacked on the substrate alternately with the electrode patterns. The stack structures are spaced apart by the block separation area in the third direction. A plurality of channel structures extend through the stack structures to the substrate in the cell block area in the first direction and are connected to the substrate. A plurality of dummy channel structures extend through upper portions of each of the stack structures in the boundary area and are connected to a dummy bottom electrode pattern spaced apart from the substrate. The bridge defect is thus substantially prevented near the substrate.

Abstract: A semiconductor memory includes a substrate including a first region in which a plurality of variable resistance elements are arranged, second and third regions on different sides of the first region, a plurality of first lines disposed over the substrate and extending across the first region and the second region, a plurality of second lines disposed over the first lines and extending across the first region and the third region. The variable resistance elements are positioned at intersections of the first lines and the second lines between the first lines and the second lines, a contact plug is disposed in the third region with an upper end coupled to the second line, and a resistive material layer is interposed between the second line and the variable resistance element in the first region but not between the second line and the contact plug in the third region.

Abstract: A semiconductor device includes: an alternating stack that is disposed over a lower structure and includes gate electrodes and dielectric layers which are staked alternately; a memory stack structure that includes a channel layer extending to penetrate through the alternating stack, and a memory layer surrounding the channel layer; a source contact layer in contact with a lower outer wall of the vertical channel layer and disposed between the lower structure and the alternating stack; a source contact plug spaced apart from the memory stack structure and extending to penetrate through the alternating stack; and a sealing spacer suitable for sealing the gate electrodes and disposed between the source contact plug and the gate electrodes. The sealing spacer has an etch resistance that is different from an etch resistance of the dielectric layers.

Abstract: This technology provides an electronic device and a method for fabricating the same. An electronic device in accordance with an implementation of this document may include a substrate including a first portion in a first region and a second portion in a second region; a plurality of memory cells disposed over the first portion of the substrate; a first insulating layer extending over the second portion of the substrate and at least partially filling a space between adjacent ones of the plurality of memory cells; and a second insulating layer disposed over the first insulating layer. The first insulating layer has a dielectric constant smaller than that of the second insulating layer, a thermal conductivity smaller than that of the second insulating layer, or both.

Abstract: A nonvolatile memory device includes a semiconductor substrate, a memory array region including a plurality of word lines formed linearly along a plane having a height (h1), a plurality of linear bit lines formed linearly along a plane having a height (h2) in a direction intersecting the plurality of word lines, and a plurality of memory cells provided between an intersection portion of each of the plurality of word lines with the plurality of bit lines and each of the plurality of bit lines, and a peripheral circuit region including a plurality of linear electrodes formed linearly along a plane having a height (h1), a plurality of linear electrodes formed linearly along a plane having the height (h2) in a direction intersecting the plurality of linear electrodes, and an insulators provided at least between the plurality of linear electrodes and the plurality of linear electrodes.

Abstract: A reactive material erasure element comprising a reactive material is located between PCM cells and is in close proximity to the PCM cells. The reaction of the reactive material is trigger by a current applied by a bottom electrode which has a small contact area with the reactive material erasure element, thereby providing a high current density in the reactive material erasure element to ignite the reaction of the reactive material. Due to the close proximity of the PCM cells and the reactive material erasure element, the heat generated from the reaction of the reactive material can be effectively directed to the PCM cells to cause phase transformation of phase change material elements in the PCM cells, which in turn erases data stored in the PCM cells.

Abstract: Described herein are IC devices that include semiconductor nanoribbons stacked over one another to realize high-density three-dimensional (3D) dynamic random-access memory (DRAM). An example device includes a first semiconductor nanoribbon, a second semiconductor nanoribbon, a first source or drain (S/D) region and a second S/D region in each of the first and second nanoribbons, a first gate stack at least partially surrounding a portion of the first nanoribbon between the first and second S/D regions in the first nanoribbon, and a second gate stack, not electrically coupled to the first gate stack, at least partially surrounding a portion of the second nanoribbon between the first and second S/D regions in the second nanoribbon. The device further includes a bitline coupled to the first S/D regions of both the first and second nanoribbons.

Abstract: Metal-assisted chemical etching is employed to form a three-dimensional (3D) resistive random access memory (ReRAM) in which the etching aspect ratio limit is extended and the top trench and bottom trench CD uniformity is improved. The 3D ReRAM includes a metal catalyst located between a bitline electrode and a selector device. Further, the 3D ReRAM includes vertically stacked and spaced apart replacement wordline electrodes that are located adjacent to the bitline electrode.

Abstract: Spacer-based patterning for tight-pitch and low-variability random access memory (RAM) bit cells, and the resulting structures, are described. In an example, a semiconductor structure includes a substrate having a top layer. An array of non-volatile random access memory (RAM) bit cells is disposed on the top layer of the substrate. The array of non-volatile RAM bit cells includes columns of non-volatile RAM bit cells along a first direction and rows of non-volatile RAM bit cells along a second direction orthogonal to the first direction. A plurality of recesses is in the top layer of the substrate, along the first direction between columns of the array of non-volatile RAM bit cells.

Abstract: A semiconductor device is described, which includes a first transistor, a second transistor, and a capacitor. The second transistor and the capacitor are provided over the first transistor so as to overlap with a gate of the first transistor. A semiconductor layer of the second transistor and a dielectric layer of the capacitor are directly connected to the gate of the first transistor. The second transistor is a vertical transistor, where its channel direction is perpendicular to an upper surface of a semiconductor layer of the first transistor.

Abstract: A memory-containing die includes a three-dimensional memory array, a memory dielectric material layer located on a first side of the three-dimensional memory array, and memory-side bonding pads. A logic die includes a peripheral circuitry configured to control operation of the three-dimensional memory array, logic dielectric material layers located on a first side of the peripheral circuitry, and logic-side bonding pads included in the logic dielectric material layers. The logic-side bonding pads includes a pad-level mesh structure electrically connected to a source power supply circuit within the peripheral circuitry and containing an array of discrete openings therethrough, and discrete logic-side bonding pads. The logic-side bonding pads are bonded to a respective one, or a respective subset, of the memory-side bonding pads. The pad-level mesh structure can be used as a component of a source power distribution network.

Abstract: A phase-change storage element including, in a first portion, a stack of amorphous layers, the thickness of each layer in the stack being smaller than or equal to 5 nm.

Abstract: The disclosure provides a circuit structure and method to provide self-aligned contacts in a zero-via conductor layer. The structure may include a device layer including a first contact to a first source/drain region, and a second contact to a second source/drain region, the first and second source/drain regions being separated by a transistor gate. A zero-via layer of the circuit structure may include: a first via conductor positioned on the first contact and self-aligned with an overlying metal level in a first direction; and a second via conductor positioned on the second contact and self-aligned with the overlying metal level in a second direction, the second direction being orthogonal to the first direction.

Abstract: A semiconductor memory device includes a first conductive layer, second conductive layers extending in a first direction and stacked above the first conductive layer in a second direction, a third conductive layer between the first conductive layer and the second conductive layers, a memory pillar extending inside the second conductive layers in the second direction, a first insulating layer that isolates the second conductive layers in a third direction, and second insulating layers spaced from an end of the first insulating layer and extending in the third direction. The second insulating layers are spaced from an extension line of the first insulating layer that extends in the first direction. The first conductive layer includes a region that overlaps in the second direction a region where extension lines of the first and second insulating layers intersect, and the third conductive layer does not overlap this intersection region in the second direction.

Abstract: An RRAM structure includes a substrate. An RRAM is embedded in the substrate. The RRAM includes a bottom electrode, a metal oxide layer and a top electrode. A first doped region is embedded in the substrate and surrounds the bottom electrode. A transistor is disposed on the substrate and at one side of the RRAM. The transistor includes a gate structure on the substrate. A source is disposed in the substrate and at one side of the gate structure. A drain is disposed in the substrate and at another side of the gate structure. The first doped region contacts the drain.

Abstract: An alternating stack of insulating layers and sacrificial material layers is formed over a substrate. Memory openings are formed through the alternating stack. Protruding tip portions are formed on each of the sacrificial material layers around the memory openings. A plurality of insulating spacers is formed within each memory opening between each vertically neighboring pair of tip portions of the sacrificial material layers. A phase change memory material and a vertical bit line are formed within each of the memory openings. The phase change memory material can be formed as a vertical stack of discrete annular phase change memory material portions, or can be formed as a continuous phase change memory material layer. Each of the sacrificial material layer can be replaced by an electrically conductive layer.

Abstract: A memory device includes: a first conductor extending in parallel with a first axis; a first selector material comprising a first portion that extends along a first sidewall of the first conductor; a second selector material comprising a first portion that extends along the first sidewall of the first conductor; a first variable resistive material comprising a portion that extends along the first sidewall of the first conductor; and a second conductor extending in parallel with a second axis substantially perpendicular to the first axis, wherein the first portion of the first selector material, the first portion of the second selector material, and the portion of the first variable resistive material are arranged along a first direction in parallel with a third axis substantially perpendicular to the first axis and second axis.

Abstract: A staggered memory cell architecture staggers memory cells on opposite sides of a shared bit line preserves memory cell density, while increasing the distance between such memory cells, thereby reducing the possibility of a disturb. In one implementation, the memory cells along a first side of a shared bit line are connected to a set of global word lines provided underneath the memory structure, while the memory cells on the other side of the shared bit line—which are staggered relative to the memory cells on the first side—are connected to global word lines above the memory structure.

Abstract: A semiconductor device is described, which includes a first transistor, a second transistor, and a capacitor. The second transistor and the capacitor are provided over the first transistor so as to overlap with a gate of the first transistor. A semiconductor layer of the second transistor and a dielectric layer of the capacitor are directly connected to the gate of the first transistor. The second transistor is a vertical transistor, where its channel direction is perpendicular to an upper surface of a semiconductor layer of the first transistor.

Abstract: A method to control a memory cell in a memory device, where the memory cell includes a switch, a memory element and a negative resistance device coupled in series, the method includes: determine whether the memory cell is in a read operation or not; during the read operation in the memory cell, apply a read voltage greater than a predetermined threshold voltage of the negative resistance device for making the negative resistance device entering into a negative resistance state. A memory device that includes a memory cell array is also provided.

Abstract: A memory device is disclosed. The memory device includes a bottom contact, and a memory layer connected to the bottom contact, where the memory layer has a variable resistance. The memory device also includes a top electrode on the memory layer, where the top electrode and the memory layer cooperatively form a heterojunction memory structure. The memory device also includes a top contact on the top electrode, and a first barrier layer, including a first oxide material and a second oxide material, where the first oxide material is different from the second oxide material, and where the first barrier layer is between one of A) the memory layer and the bottom contact, and B) the top electrode and the top contact, where the first barrier layer is configured to substantially prevent the conduction of ions or vacancies therethrough.