A method of integrating a phase change switch (PCS) into a Bipolar (Bi)/Complementary Metal Oxide Semiconductor (CMOS) (BiCMOS) process, comprises providing a base structure including BiCMOS circuitry on a semiconductor substrate, and forming on the base structure a dielectric contact window layer having metal through-plugs that contact the BiCMOS circuitry. The method includes constructing the PCS on the contact window layer. The PCS includes: a phase change region, between ohmic contacts on the phase change region, to operate as a switch controlled by heat. The method further includes forming, on the contact window layer and the PCS, a stack of alternating patterned metal layers and dielectric layers that interconnect the patterned metal layers, such that the stack connects a first of the ohmic contacts to the BiCMOS circuitry and provides connections to a second of the ohmic contacts and to the resistive heater.

Various embodiments of the present disclosure are directed towards a memory cell comprising a high electron affinity dielectric layer at a bottom electrode. The high electron affinity dielectric layer is one of multiple different dielectric layers vertically stacked between the bottom electrode and a top electrode overlying the bottom electrode. Further, the high electrode electron affinity dielectric layer has a highest electron affinity amongst the multiple different dielectric layers and is closest to the bottom electrode. The different dielectric layers are different in terms of material systems and/or material compositions. It has been appreciated that by arranging the high electron affinity dielectric layer closest to the bottom electrode, the likelihood of the memory cell becoming stuck during cycling is reduced at least when the memory cell is RRAM. Hence, the likelihood of a hard reset/failure bit is reduced.

A semiconductor storage device capable of achieving low power and high integration is provided. A non-volatile semiconductor memory of the disclosure includes a memory cell array. The memory cell array has a NOR array with a NOR flash memory structure and a variable resistance array with a variable resistance memory structure formed on a substrate. An entry gate is formed between the NOR array and the variable resistance array. When the NOR array is accessed, the entry gate separates the variable resistance array from the NOR array.

Methods, systems, and devices for techniques that support sidewall structures for memory cells in vertical structures are described. A memory cell may include a first electrode, a second electrode, and a self-selecting storage element between the first electrode and the second electrode. The self-selecting storage element may extend between the first electrode and the second electrode in a direction that is parallel with a plane defined by the substrate. The self-selecting storage element may also include a bulk region and a sidewall region. The bulk region may include a chalcogenide material having a first composition, and the sidewall region may include the chalcogenide material having a second composition that is different than the first composition. Also, the sidewall region may extend between the first electrode and the second electrode.

A 3D semiconductor device, the device including: a first level including a first single crystal layer, the first level including a plurality of first transistors and at least one metal layer, where the at least one metal layer overlays the first single crystal layer, and where the at least one metal layer includes interconnects between the plurality of first transistors, the interconnects between the plurality of first transistors include forming first control circuits; a second level overlaying the at least one metal layer, the second level including a plurality of second transistors; a third level overlaying the second level, the third level including a plurality of third transistors, where the second level includes a plurality of first memory cells, the first memory cells each including at least one of the plurality of second transistors, where the third level includes a plurality of second memory cells, the second memory cells each including at least one of the plurality of third transistors, where at least one of the plurality of second memory cells is at least partially atop of the first control circuits, where the first control circuits are adapted to control data written to at least one of the plurality of second memory cells; and where the plurality of second transistors are horizontally oriented transistors.

One illustrative method disclosed herein includes forming at least one first layer of insulating material above an upper surface of a top electrode of a memory cell, forming a patterned etch stop layer above the at least one first layer of insulating material, wherein the patterned etch stop layer has an opening that is positioned vertically above at least a portion of the upper surface of the top electrode and forming at least one second layer of insulating material above an upper surface of the etch stop layer. The method also includes forming a conductive contact opening that extends through the etch stop layer to expose at least a portion of the upper surface of the top electrode and forming a conductive contact structure in the conductive contact opening, wherein the conductive contact structure is conductively coupled to the upper surface of the top electrode.

A transistor may be provided by forming, in a forward order or in a reverse order, a gate electrode, a semiconducting metal oxide liner, a gate dielectric, and an active layer over a substrate, and by forming a source electrode and a drain electrode on end portions of the active layer. The semiconducting metal oxide liner comprises a thin semiconducting metal oxide material that functions as a hydrogen barrier material.

A semiconductor device including: a first silicon layer including a first single crystal silicon and a plurality of first transistors; a first metal layer disposed over the first silicon layer; a second metal layer disposed over the first metal layer; a third metal layer disposed over the second metal layer; a second level including a plurality of second transistors, the second level disposed over the third metal layer; a fourth metal layer disposed over the second level; a fifth metal layer disposed over the fourth metal layer, a connection path from the fifth metal layer to the second metal layer, where the connection path includes a via disposed through the second level, where the via has a diameter of less than 450 nm, where the fifth metal layer includes a global power distribution grid, and where a typical thickness of the fifth metal layer is greater than a typical thickness of the second metal layer by at least 50%.

Some embodiments relate to a memory device. The memory device includes a bottom electrode overlying a substrate. A data storage layer overlies the bottom electrode. A top electrode overlies the data storage layer. A conductive bridge is selectively formable within the data storage layer to couple the bottom electrode to the top electrode. A diffusion barrier layer is disposed between the data storage layer and the top electrode.

A method for fabricating memory device is provided. The method includes forming a transistor on a substrate. Further, a contact structure is formed on a source/drain region of the transistor. A conductive layer is formed on the contact structure. Four memory structures are formed on the conductive layer to form a quadrilateral structure.