A variable resistance memory device includes lower conductive lines extending in a first direction on a substrate and spaced apart from each other in a second direction crossing the first direction, peripheral transistors on the substrate and arranged under the lower conductive lines in a third direction crossing the first direction and the second direction, and lower contacts electrically connecting the lower conductive lines to the peripheral transistors and extending in the third direction. Each of the lower conductive lines includes a first lower extending portion extending in the first direction, a second lower extending portion offset in the second direction from the first lower extending portion and extending in the first direction, and a lower connecting portion connecting the first lower extending portion to the second lower extending portion. Each of the lower contacts is in the lower connecting portion of a respective one of the lower conductive lines.

Provided are memory cells, such as resistive random access memory (ReRAM) cells, each cell having multiple metal oxide layers formed from different oxides, and methods of manipulating and fabricating these cells. Two metal oxides used in the same cell have different dielectric constants, such as silicon oxide and hafnium oxide. The memory cell may include electrodes having different metals. Diffusivity of these metals into interfacing metal oxide layers may be different. Specifically, the lower-k oxide may be less prone to diffusion of the metal from the interfacing electrode than the higher-k oxide. The memory cell may be formed to different stable resistive levels and then resistively switched at these levels. Each level may use a different switching power. The switching level may be selected a user after fabrication of the cell and in, some embodiments, may be changed, for example, after switching the cell at a particular level.

A single memory cell has the functions of a storage element and a selector. The memory cell includes a P-type layer, a tunneling structure and an N-type layer. The tunneling structure is formed on the P-type layer. The N-type layer is formed on the tunneling structure. The tunneling structure is a stack structure including a first material layer, a second material layer and a third material layer. By adjusting a bias voltage that is applied to the P-type layer and the N-type layer, the tunneling structure is controlled to be in the amorphous state or the crystalline state. Consequently, the memory cell has the memorizing and storing functions. The memory cell has the P-type layer, the tunneling structure and the N-type layer. By adjusting the bias voltage, the function of the selector is achieved.

Forming a semiconductor device includes forming a first conductive line on a substrate, forming a memory cell including a switching device and a data storage element on the first conductive line, and forming a second conductive line on the memory cell. Forming the switching device includes forming a first semiconductor layer, forming a first doped region by injecting a n-type impurity into the first semiconductor layer, forming a second semiconductor layer thicker than the first semiconductor layer, on the first semiconductor layer having the first doped region, forming a second doped region by injecting a p-type impurity into an upper region of the second semiconductor layer, and forming a P-N diode by performing a heat treatment process to diffuse the n-type impurity and the p-type impurity in the first doped region and the second doped region to form a P-N junction of the P-N diode in the second semiconductor layer.

Thin film 1S1R bitcells incorporating a barrier between selector and memory elements. Devices incorporating such bitcells and methods of forming such bitcells are also described. In embodiments, the selector and memory element is each a dielectric material, and advantageously a metal oxide. Between the selector and memory elements is a barrier, which is to reduce intermixing and/or reaction of selector material and memory material. Addition of a barrier layer having suitable material properties into the 1S1R stack may extend the operating lifetime of a bitcell incorporated the stack by resisting intermixing and/or reaction of the selector and memory thin film materials driven by thermal and/or electric field stresses experienced by a bitcell during operation. In embodiments, a barrier layer may include one or more material layers having a composition distinct from the material composition(s) of the selector and memory elements.

Methods, systems, and devices for a three-dimensional memory array are described. Memory cells may transform when exposed to elevated temperatures, including elevated temperatures associated with a read or write operation of a neighboring cell, corrupting the data stored in them. To prevent this thermal disturb effect, memory cells may be separated from one another by thermally insulating regions that include one or several interfaces. The interfaces may be formed by layering different materials upon one another or adjusting the deposition parameters of a material during formation. The layers may be created with planar thin-film deposition techniques, for example.

A variable resistance memory device includes a pattern of one or more first conductive lines, a pattern of one or more second conductive lines, and a memory structure between the first and second conductive lines. The pattern of first conductive lines extends in a first direction on a substrate, and the first conductive lines extend in a second direction crossing the first direction. The pattern of second conductive lines extends in the second direction on the first conductive lines, and the second conductive lines extend in the first direction. The memory structure vertically overlaps a first conductive line and a second conductive line. The memory structure includes an electrode structure, an insulation pattern on a central upper surface of the electrode structure, and a variable resistance pattern on an edge upper surface of the electrode structure. The variable resistance pattern at least partially covers a sidewall of the insulation pattern.

A semiconductor storage device includes lower and upper bit lines, word lines between the bit lines, and memory cells between the bit lines and the word lines. The memory cells are divided into logical slices and a memory cell from each logical slice is selected when carrying out a read or write operation. A first logical slice includes memory cells, each of which is between one of two bit lines and one of three word lines that are adjacent to each other. The two bit lines include one lower bit line and one upper bit line. A second logical slice includes memory cells, each of which is between one of three bit lines and one of three word lines that are not adjacent to each other. The three bit lines include one lower bit line and two upper bit lines.

A variable resistance memory device including a selection pattern; an intermediate electrode contacting a first surface of the selection pattern; a variable resistance pattern on an opposite side of the intermediate electrode relative to the selection pattern; and a first electrode contacting a second surface of the selection pattern and including a n-type semiconductor material, the second surface of the selection pattern being opposite the first surface thereof.

A three-dimensional memory device includes an alternating stack of electrically conductive layers and insulating layers located over a top surface of a substrate, semiconductor local bit lines extending perpendicular to the top surface of the substrate, and resistivity switching memory elements located at each overlap region between the electrically conductive layers and the semiconductor local bit lines. Each of the semiconductor local bit lines includes a plurality of drain regions located at each level of the electrically conductive layers, and having a doping of a first conductivity type, and a semiconductor channel vertically extending from a level of a bottommost electrically conductive layer within the alternating stack to a level of a topmost electrically conductive layer within the alternating stack, and contacting the plurality of drain regions within the semiconductor local bit line.