Kabushiki Kaisha Toshiba

Kioxia Corporation

Toshiba Memory Corporation

Kenji Gomikawa

Mitsuhiro Noguchi

Hiroyuki Kutsukake

Takashi Aoi

Koji Hosono

Masaru Koyanagi

Dai Nakamura

Takeshi Shimane

Yoshiko Kato

Masato Endo

Takuya Futatsuyama

Koji Kato

Kikuko Sugimae

Tadashi Iguchi

Norihisa Arai

Kenji Sawamura

Haruhiko Koyama

Shoichi Watanabe

Takayuki Toba

Kanae Uchida

Tomoaki Hatano

A non-volatile semiconductor storage device includes: a memory cell array having memory cells arranged therein, the memory cells storing data in a non-volatile manner; and a plurality of transfer transistors transferring a voltage to the memory cells, the voltage to be supplied for data read, write and erase operations with respect to the memory cells. Each of the transfer transistors includes: a gate electrode formed on a semiconductor substrate via a gate insulation film; and diffusion layers formed to sandwich the gate electrode therebetween and functioning as drain/source layers. Upper layer wirings are provided above the diffusion layers and provided with a predetermined voltage to prevent depletion of the diffusion layers at least when the transfer transistors become conductive.

Non-volatile semiconductor storage device

A semiconductor device includes MOS transistors, capacitor elements, a voltage generating circuit, a contact plug, and a memory cell. The MOS transistor and the capacitor element are formed on a first one of the element regions and a second one of the element regions, respectively. In the voltage generating circuit, current paths of the MOS transistors are series-connected and the capacitor elements are connected to the source or drain of the MOS transistors. The contact plug is formed on the source or the drain to connect the MOS transistors or one of the MOS transistors and one of the capacitor elements. A distance between the gate and the contact plug both for a first one of the MOS transistors located in the final stage in the series connection is larger than that for a second one of the MOS transistors located in the initial stage in the series connection.

Semiconductor device including memory cell having charge accumulation layer

A memory includes a first word line which is connected to a control gate electrode of a first memory cell, a second word line which is connected to a control gate electrode of a second memory cell, a potential transfer line which is connected to both of the first and second word lines, a first N-channel MOS transistor which is connected between the first word line and the potential transfer line, and a second N-channel MOS transistor which is connected between the second word line and the potential transfer line. A control circuit supplies a first potential with a plus value to a semiconductor substrate, and supplies a second potential with the plus value lower than the first potential to the potential transfer line, to turn the first N-channel MOS transistor on, and to turn the second N-channel MOS transistor off, in erasing data of the first memory cell.

Potential relationship in an erasing operation of a nonvolatile semiconductor memory

A semiconductor device includes a semiconductor substrate, an element isolation insulating film dividing an upper portion of the substrate into a plurality of first active regions, a source layer and a drain layer, a gate electrode, a gate insulating film, a first punch-through stopper layer, and a second punch-through stopper layer. The source layer and the drain layer are formed in spaced to each other in an upper portion of each of the first active regions. The first punch-through stopper layer is formed in a region of the first active region directly below the source layer and the second punch-through stopper layer is formed in a region of the first active region directly below the drain layer. The first punch-through stopper layer and the second punch-through stopper layer each has an effective impurity concentration higher than the semiconductor substrate. The first punch-through stopper layer and the source layer are separated in the channel region. The second punch-through stopper layer and the drain layer are separated in the channel region.

Semiconductor device and method for manufacturing the same

A semiconductor memory device includes a first transistor. The first transistor includes a gate electrode, a channel region, a source region, a source region, an overlapping region, a contact region, and an impurity diffusion region. The channel region has a first impurity concentration. The source and drain regions have a second impurity concentration. The overlapping region is formed in the semiconductor layer where the channel region overlaps the source region and the drain region, and has a third impurity concentration. The contact region has a fourth impurity concentration. The impurity diffusion region has a fifth impurity concentration higher than the second impurity concentration and lower than the fourth impurity concentration. The impurity diffusion region is in contact with the contact region and away from the overlapping region and positioned at least in a region between the contact region and the overlapping region.

Depletion MOS transistor and enhancement MOS transistor

A peripheral circuit area is formed around a memory cell array area. The peripheral circuit area has element regions, an element isolation region isolating the element regions, and field-effect transistor formed in each of the element regions and including a gate electrode extending in a channel width direction, on a semiconductor substrate. An end portion and a corner portion of the gate electrode are on the element isolation region. A radius of curvature of the corner portion of the gate electrode is smaller than a length from the end portion of the element region in the channel width direction to the end portion of the gate electrode in the channel width direction, and is less than 85 nm.

Nonvolatile semiconductor memory device with reduced size of peripheral circuit area

A peripheral circuit includes at least a first transistor. The first transistor comprises a gate electrode formed on a surface of a semiconductor layer via a gate insulating film. A channel region of a first conductivity type having a first impurity concentration is formed on a surface of the semiconductor layer directly below and in the vicinity of the gate electrode. A source-drain diffusion region of the first conductivity type is formed on the surface of the semiconductor layer to sandwich the gate electrode and has a second impurity concentration greater than the first impurity concentration. An overlapping region of the first conductivity type is formed on the surface of the semiconductor layer directly below the gate electrode where the channel region and the source-drain diffusion region overlap. The overlapping region has a third impurity concentration greater than the second impurity concentration.

Non-volatile semiconductor memory device and depletion-type MOS transistor

A first select transistor is connected to one end of a plurality of memory cell transistors that are serially connected. A second select transistor is connected to the other end of the serially connected memory cell transistors. A first impurity diffusion region is formed in a semiconductor substrate and constitutes a first main electrode of the first select transistor. A second impurity diffusion region is formed in the semiconductor substrate and constitutes a second main electrode of the second select transistor. A depth of the first impurity diffusion region is greater than a depth of the second impurity diffusion region.

Nonvolatile semiconductor memory device

A memory cell includes a floating gate electrode, a first inter-electrode insulating film and a control gate electrode. A peripheral transistor includes a lower electrode, a second inter-electrode insulating film and an upper electrode. The lower electrode and the upper electrode are electrically connected via an opening provided on the second inter-electrode insulating film. The first and second inter-electrode insulating films include a high-permittivity material, the first inter-electrode insulating film has a first structure, and the second inter-electrode insulating film has a second structure different from the first structure.

Growing community of inventors

Yokohama, Japan

Kenji Gomikawa