Provided are a weighting device that may be driven at a low voltage and is capable of embodying multi-level weights, a neural network, and a method of operating the weighting device. The weighting device includes a switching layer that may switch between a high resistance state and a low resistance state based on a voltage applied thereto and a charge trap material layer that traps or discharges charges according to a resistance state of the switching layer. The weighting device may be used for controlling a weight in a neural network.

A method for forming a semiconductor device structure is provided. The method includes forming a mask layer over a substrate. The method includes forming a first isolation structure and a second isolation structure passing through the mask layer and penetrating into the substrate. The method includes thinning the mask layer to expose a first portion of the first isolation structure and a second portion of the second isolation structure. The method includes partially removing the first portion, the second portion, the third portion, and the fourth portion. The method includes removing the thinned mask layer. The method includes forming a first gate over the substrate and between the first isolation structure and the second isolation structure. The method includes forming a dielectric layer over the first gate. The method includes forming a second gate over the dielectric layer and above the first gate.

A semiconductor memory cell includes a floating body region configured to be charged to a level indicative of a state of the memory cell; a first region in electrical contact with said floating body region; a second region in electrical contact with said floating body region and spaced apart from said first region; and a gate positioned between said first and second regions. The cell may be a multi-level cell. Arrays of memory cells are disclosed for making a memory device. Methods of operating memory cells are also provided.

Semiconductor structures are provided. The semiconductor structure includes a substrate and a floating gate structure formed over the substrate. The semiconductor structure further includes a dielectric structure formed over the floating gate structure and a control gate structure formed over the dielectric structure. The semiconductor structure further includes a first spacer formed over a lower portion of a sidewall of the control gate structure and an upper spacer formed over an upper portion of the sidewall of the control gate structure. In addition, a portion of the control gate structure is in direct contact with the upper spacer.

Device architectures based on trapping and de-trapping holes or electrons and/or recombination of both types of carriers are obtained by carrier trapping either in near-interface deep ambipolar states or in quantum wells/dots, either serving as ambipolar traps in semiconductor layers or in gate dielectric/barrier layers. In either case, the potential barrier for trapping is small and retention is provided by carrier confinement in the deep trap states and/or quantum wells/dots. The device architectures are usable as three terminal or two terminal devices.

Methods of maintaining a state of a memory cell without interrupting access to the memory cell are provided, including applying a back bias to the cell to offset charge leakage out of a floating body of the cell, wherein a charge level of the floating body indicates a state of the memory cell; and accessing the cell.

A method of manufacturing the semiconductor device includes forming a first gate member on a semiconductor substrate through a gate insulating film, forming a spacer on the first gate member, flattening a surface of the spacer, forming a first gate by partially etching the first gate member using the spacer as a mask, forming a second gate member so as to cover the first gate and the spacer having the flattened surface, forming a first insulating film on a surface of the second gate member, and forming a second gate by causing the second gate member to retreat while removing the first insulating film by etching, and the corresponding semiconductor device.

A method of forming a memory device by forming spaced apart first and second regions with a channel region therebetween, forming a floating gate over and insulated from a first portion of the channel region, forming a control gate over and insulated from the floating gate, forming an erase gate over and insulated from the first region, and forming a select gate over and insulated from a second portion of the channel region. Forming of the floating gate includes forming a first insulation layer on the substrate, forming a first conductive layer on the first insulation layer, and performing two separate etches to form first and second trenches through the first conductive layer. A sidewall of the first conductive layer at the first trench has a negative slope and a sidewall of the first conductive layer at the second trench is vertical.

Provided is a highly integrated semiconductor device which can hold data and includes a NAND cell array. Each of the plurality of memory cells of the NAND cell array includes a first transistor, a second transistor, a first terminal, a second terminal, a third terminal, and a fourth terminal. The first terminal is electrically connected to one electrode connected to a channel region of the first transistor. The second terminal is electrically connected to the other electrode connected to the channel region of the first transistor. The third terminal is electrically connected to a gate electrode of the second transistor. The fourth terminal is electrically connected to one electrode connected to a channel region of the second transistor. A gate electrode of the first transistor is in contact with the other electrode connected to the channel region of the second transistor. A string of the plurality of memory cells is formed by connecting the first terminals and the second terminals.

A semiconductor memory cell and arrays of memory cells are provided In at least one embodiment, a memory cell includes a substrate having a top surface, the substrate having a first conductivity type selected from a p-type conductivity type and an n-type conductivity type; a first region having a second conductivity type selected from the p-type and n-type conductivity types, the second conductivity type being different from the first conductivity type, the first region being formed in the substrate and exposed at the top surface; a second region having the second conductivity type, the second region being formed in the substrate, spaced apart from the first region and exposed at the top surface; a buried layer in the substrate below the first and second regions, spaced apart from the first and second regions and having the second conductivity type; a body region formed between the first and second regions and the buried layer, the body region having the first conductivity type; a gate positioned between the first and second regions and above the top surface; and a nonvolatile memory configured to store data upon transfer from the body region.