An object is to provide a semiconductor device having electrical characteristics such as high withstand voltage, low reverse saturation current, and high on-state current. In particular, an object is to provide a power diode and a rectifier which include non-linear elements. An embodiment of the present invention is a semiconductor device including a first electrode, a gate insulating layer covering the first electrode, an oxide semiconductor layer in contact with the gate insulating layer and overlapping with the first electrode, a pair of second electrodes covering end portions of the oxide semiconductor layer, an insulating layer covering the pair of second electrodes and the oxide semiconductor layer, and a third electrode in contact with the insulating layer and between the pair of second electrodes. The pair of second electrodes are in contact with end surfaces of the oxide semiconductor layer.

A semiconductor rectifier device comprises: an epitaxial layer having a top surface and a bottom surface; a first trench comprising a first side wall, a second side wall, and a first bottom surface; a second trench adjacent to the first trench, the second trench comprising a third side wall, a fourth side wall, and a second bottom surface; a first doped region abutting against the first side wall and at least a part of the first bottom surface of the first trench; a second doped region adjacent to and separated from the first doped region, wherein the second doped region abuts against the third side wall, the fourth side wall and the second bottom surface of the second trench; a gate structure disposed on the top surface between the first trench and the second trench; and a contact metal layer disposed on the top surface of the epitaxial layer.

As a display device has a higher definition, the number of pixels, gate lines, and signal lines are increased. When the number of the gate lines and the signal lines are increased, a problem of higher manufacturing cost, because it is difficult to mount an IC chip including a driver circuit for driving of the gate and signal lines by bonding or the like. A pixel portion and a driver circuit for driving the pixel portion are provided over the same substrate, and at least part of the driver circuit includes a thin film transistor using an oxide semiconductor interposed between gate electrodes provided above and below the oxide semiconductor. Therefore, when the pixel portion and the driver portion are provided over the same substrate, manufacturing cost can be reduced.

A semiconductor device includes an active pattern including a channel region. The channel region is disposed between first and second source/drain patterns that are spaced apart from each other in a first direction. The channel region is configured to connect the first and second source/drain patterns to each other. A gate electrode is disposed on a bottom surface of the active pattern and is disposed between the first and second source/drain patterns. An upper interconnection line is disposed on a top surface of the active pattern opposite to the bottom surface of the active pattern and is connected to the first source/drain pattern.

A semiconductor device including a substrate including a first region and a second region, a first active pattern extending in a first direction on the first region, a second active pattern extending in the first direction on the second region, a wall structure extending in the first direction between the first region and the second region and separating the first active pattern and the second active pattern from each other, a first gate structure intersecting the first active pattern on the first region, a first two-dimensional (2D) channel layer including a first transition metal dichalcogenide between the first active pattern and the first gate structure, a second gate structure intersecting the second active pattern on the second region, and a second 2D channel layer including a second transition metal dichalcogenide between the second active pattern and the second gate structure may be provided.

According to one aspect of the present disclosure, a semiconductor device is provided. The semiconductor device may include a stacked layer and a top select gate layer located on the stacked layer. The semiconductor device may include a gate-line structure extending through the top select gate layer and the stacked layer. A portion of the gate-line structure that extends through the top select gate layer may be a first isolation structure, and the first isolation structure may include a contact layer in contact with the top select gate layer. The semiconductor device may include a channel structure extending through the stacked layer and a first dielectric layer located on the top select gate layer, where the first dielectric layer and the contact layer comprise different insulating materials. The semiconductor device may include a channel local contact extending through the first dielectric layer and corresponding to the channel structure.

A semiconductor rectifier device comprises: an epitaxial layer having a top surface and a bottom surface; a first trench comprising a first side wall, a second side wall, and a first bottom surface; a second trench adjacent to the first trench, the second trench comprising a third side wall, a fourth side wall, and a second bottom surface; a first doped region abutting against the first side wall and at least a part of the first bottom surface of the first trench; a second doped region adjacent to and separated from the first doped region, wherein the second doped region abuts against the third side wall, the fourth side wall and the second bottom surface of the second trench; a gate structure disposed on the top surface between the first trench and the second trench; and a contact metal layer disposed on the top surface of the epitaxial layer.

A transistor whose channel region includes an oxide semiconductor is used as a pull down transistor. The band gap of the oxide semiconductor is 2.0 eV or more, preferably 2.5 eV or more, more preferably 3.0 eV or more. Thus, hot carrier degradation in the transistor can be suppressed. Accordingly, the circuit size of the semiconductor device including the pull down transistor can be made small. Further, a gate of a pull up transistor is made to be in a floating state by switching of on/off of the transistor whose channel region includes an oxide semiconductor. Note that when the oxide semiconductor is highly purified, the off-state current of the transistor can be 1 aA/m (110.sup.18 A/m) or less. Therefore, the drive capability of the semiconductor device can be improved.

A semiconductor device includes a pattern structure; a stack structure including gate layers stacked in a first region on the pattern structure and extending into a second region; a memory vertical structure penetrating the stack structure in the first region; gate contact plugs electrically connected to the gate layers in the second region; and a first peripheral contact plug spaced apart from the gate layers, the gate layers including a first gate layer, the gate contact plugs including a first gate contact plug electrically connected to the first gate layer, side surfaces of the first gate contact plug and the first peripheral contact plug having different numbers of upper bending portions, and the number of upper bending portions of the side surface of the first gate contact plug being greater than the number of upper bending portions of the side surface of the first peripheral contact plug.

Structures and formation methods of a semiconductor device structure are provided. The semiconductor device structure includes a plurality of nanostructures over a substrate, and a gate electrode surrounding the nanostructures. The semiconductor device structure includes a source/drain portion adjacent to the gate electrode, and a semiconductor layer between the gate electrode and the source/drain portion.