An improved switching material for forming a composite article over a substrate is disclosed. A first volume of nanotubes is combined with a second volume of nanoscopic particles in a predefined ration relative to the first volume of nanotubes to form a mixture. This mixture can then be deposited over a substrate as a relatively thick composite article via a spin coating process. The composite article may possess improved switching properties over that of a nanotube-only switching article. A method for forming substantially uniform nanoscopic particles of carbon, which contains one or more allotropes of carbon, is also disclosed.

Provided is a nonvolatile memory device. The nonvolatile memory device includes: first and second electrodes spaced from each other; at least one nano crystal layer disposed between the first and second electrodes; and first and second material layers respectively disposed between the first and second electrodes and the nano crystal layer and having a bistable conductive property, wherein the first and second material layers are formed asymmetrical to each other.

A conjugated polymer layer with a built-in diode is formed by providing a first metal-chalcogenide layer over a bottom electrode. Subsequently, a second metal-chalcogenide layer is provided over and in contact with the first metal-chalcogenide layer. The first metal-chalcogenide layer has a first conductivity type and the second metal-chalcogenide layer has a second conductivity type. The plane of contact between the first and second metal-chalcogenide layers creates the p-n junction of the built-in diode. Then a polymer layer is selectively deposited on the second metal-chalcogenide layer. The second metal-chalcogenide layer provides ions to the polymer layer to change its resistivity. A top electrode is then provided over the polymer layer. An exemplary memory cell may have the following stacked structure: first electrode/n-type semiconductor/p-type semiconductor/conjugated polymer/second electrode.

A semiconductor memory device in an embodiment includes a semiconductor layer, a control gate electrode, an organic molecular layer provided between the semiconductor layer and the control gate electrode, and a first insulating layer provided between the organic molecular layer and the semiconductor layer, the first insulating layer having a first layer containing alkyl chains and a second layer containing siloxane, the second layer being provided between the first layer and the organic molecular layer.

A nonvolatile three-terminal element is provided that operates by controlling a bandgap in an electron state of a graphene-based material. An ion conductor (5) having hydrogen ion or oxygen ion conductivity is provided between graphene oxide or graphene (hereinafter, referred to as GO) (6), and a gate electrode (1). In addition, a drain electrode (2) and a source electrode (3) are provided on a GO (6) side.

A conjugated polymer layer with a built-in diode is formed by providing a first metal-chalcogenide layer over a bottom electrode. Subsequently, a second metal-chalcogenide layer is provided over and in contact with the first metal-chalcogenide layer. The first metal-chalcogenide layer has a first conductivity type and the second metal-chalcogenide layer has a second conductivity type. The plane of contact between the first and second metal-chalcogenide layers creates the p-n junction of the built-in diode. Then a polymer layer is selectively deposited on the second metal-chalcogenide layer. The second metal-chalcogenide layer provides ions to the polymer layer to change its resistivity. A top electrode is then provided over the polymer layer. An exemplary memory cell may have the following stacked structure: first electrode/n-type semiconductor/p-type semiconductor/conjugated polymer/second electrode.

Methods for passivating a nanotube fabric layer within a nanotube switching device to prevent or otherwise limit the encroachment of an adjacent material layer are disclosed. In some embodiments, a sacrificial material is implanted within a porous nanotube fabric layer to fill in the voids within the porous nanotube fabric layer while one or more other material layers are applied adjacent to the nanotube fabric layer. Once the other material layers are in place, the sacrificial material is removed. In other embodiments, a non-sacrificial filler material (selected and deposited in such a way as to not impair the switching function of the nanotube fabric layer) is used to form a barrier layer within a nanotube fabric layer. In other embodiments, individual nanotube elements are combined with and nanoscopic particles to limit the porosity of a nanotube fabric layer.

A variable resistance memory device including a stack including insulating sheets and conductive sheets, which are alternatingly stacked on a substrate, the stack including a vertical hole vertically penetrating therethrough, a bit line on the stack, a conductive pattern electrically connected to the bit line and vertically extending in the vertical hole, and a resistance varying layer between the conductive pattern and an inner side surface of the stack defining the vertical hole may be provided. The resistance varying layer may include a first carbon nanotube electrically connected to the conductive sheets, and a second carbon nanotube electrically connected to the conductive pattern.

A variable resistance memory device including a stack including insulating sheets and conductive sheets, which are alternatingly stacked on a substrate, the stack including a vertical hole vertically penetrating therethrough, a bit line on the stack, a conductive pattern electrically connected to the bit line and vertically extending in the vertical hole, and a resistance varying layer between the conductive pattern and an inner side surface of the stack defining the vertical hole may be provided. The resistance varying layer may include a first carbon nanotube electrically connected to the conductive sheets, and a second carbon nanotube electrically connected to the conductive pattern.

A method of forming an RRAM cell structure is provided. The method includes forming dummy features over a substrate, and the dummy features have a gap therebetween. The method also includes depositing an oxide layer over the dummy features while forming a first V-shaped valley on the oxide layer. The method further includes partially planarizing the oxide layer while leaving the first V-shaped valley. In addition, the method includes forming a first electrode over the oxide layer while forming a second V-shaped valley on the first electrode. The method further includes forming a resistance variable layer over the first electrode in a conformal manner. The method still includes forming a second electrode over the resistance variable layer.