A semiconductor metal-oxide-semiconductor field effect transistor (MOSFET) with increased on-state current obtained through a parasitic bipolar junction transistor (BJT) of the MOSFET. Methods of operating the MOSFET as a memory cell or a memory array select transistor are provided.

A thermally optimized phase change memory cell includes a phase change material element disposed between first and second electrodes. The second electrode includes a thermally insulating region having a first thermal resistivity over the first electrode and a metallic contact region interposed between the phase change material element and the thermally insulating region, where the metallic contact layer has a second thermal resistivity lower than the first thermal resistivity.

Bipolar transistors and MOS transistors are formed in a common process. A semiconductor layer is arranged on an insulating layer. On a side of the bipolar transistors: an insulating region including the insulating layer is formed; openings are etched through the insulating region to delimit insulating walls; the openings are filled with first epitaxial portions; and the first epitaxial portions and a first region extending under the first epitaxial portions and under the insulating walls are doped. On the side of the bipolar transistors and on a side of the MOS transistors: gate structures are formed; second epitaxial portions are made; and the second epitaxial portions covering the first epitaxial portions are doped.

A method of fabricating a memory device is disclosed. In one aspect, the method comprises patterning a first conductive line extending in a first direction. The method additionally includes forming a free-standing pillar of a memory cell stack on the first conductive line after patterning the first conductive line. Forming the free-standing pillar includes depositing a memory cell stack comprising a selector material and a storage material over the conductive line and patterning the memory cell stack to form the free-standing pillar. The method further includes patterning a second conductive line on the pillar after patterning the memory cell stack, the second conductive line extending in a second direction crossing the first direction.

Semiconductor memory is provided wherein a memory cell includes a capacitorless transistor having a floating body configured to store data as charge therein when power is applied to the cell. The cell further includes a nonvolatile memory comprising a resistance change element configured to store data stored in the floating body under any one of a plurality of predetermined conditions. A method of operating semiconductor memory to function as volatile memory, while having the ability to retain stored data when power is discontinued to the semiconductor memory is described.

A memory device includes a first electrode line layer including a plurality of first electrode lines extending on a substrate in a first direction and being spaced apart from each other, a second electrode line layer including a plurality of second electrode lines extending on the first electrode line layer in a second direction that is different from the first direction and being spaced apart from each other, and a memory cell layer including a plurality of first memory cells located at a plurality of intersections between the plurality of first electrode lines and the plurality of second electrode lines, each first memory cell including a selection device layer, an intermediate electrode and a variable resistance layer that are sequentially stacked. A side surface of the variable resistance layer is perpendicular to a top surface of the substrate or inclined to be gradually wider toward an upper portion of the variable resistance layer. The first memory cell has a side surface slope so as to have a width gradually decreasing toward its upper portion.

In the cases of performing programming by forming a two-terminal-type variable resistance element on a semiconductor device, it has been difficult to control the programming, and malfunctions have often occurred. This switching element includes at least a first variable resistance element, a second variable resistance element, a first rectifying element, and a second rectifying element, one end of the first variable resistance element and one end of the second variable resistance element are respectively connected to one end of the first rectifying element and one end of the second rectifying element, and each of the rectifying elements has two terminals.

A phase change memory device or a ReRAM device is integrated with a pair of bipolar junction transistors, the pair of bipolar junction transistors being arranged in a Sziklai Darlington transistor configuration. A small unit cell footprint is obtained by pairing a vertical bipolar junction transistor with a lateral bipolar junction transistor, the memory device being electrically connected to the collector of the lateral bipolar junction transistor.

A thermally optimized phase change memory cell includes a phase change material element disposed between first and second electrodes. The second electrode includes a thermally insulating region having a first thermal resistivity over the first electrode and a metallic contact region interposed between the phase change material element and the thermally insulating region, where the metallic contact layer has a second thermal resistivity lower than the first thermal resistivity.

Memory devices and manufacturing methods thereof are presented. A memory device a substrate and a memory cell having at least one selector and a storage element. The selector includes a well of a first polarity type disposed in the substrate, a region of a second polarity type disposed over the well and in the substrate, and first and second regions of the first polarity type disposed adjacent to the region of the second polarity type. The storage element includes a programmable resistive layer disposed on the region of the second polarity type and an electrode disposed over the programmable resistive layer.