Abstract: A method for manufacturing semiconductor device according to an embodiment includes: forming an oxide semiconductor layer above a substrate; forming a gate insulating layer above the oxide semiconductor layer; forming a metal oxide layer containing aluminum as a main component above the gate insulating layer; performing a heat treatment in a state where the metal oxide layer is formed above the gate insulating layer; removing the metal oxide layer after the heat treatment; and forming a gate electrode above the gate insulating layer.

Abstract: A semiconductor device according to an embodiment includes: an oxide insulating layer; an oxide semiconductor layer; a gate electrode; a gate insulating layer; and a first insulating layer, wherein the semiconductor device is divided into a first to a third regions, a thickness of the gate insulating layer in the first region is 200 nm or more, the gate electrode contacts the first insulating layer in the first region, the oxide semiconductor layer contacts the first insulating layer in the second region, an amount of impurities contained in the oxide semiconductor layer in the second region is greater than an amount of impurities contained in the oxide semiconductor layer in the first region, and an amount of impurities contained in the oxide insulating layer in the third region is greater than an amount of impurities contained in the oxide insulating layer in the second region.

Abstract: A method for manufacturing a semiconductor device includes depositing a first metal oxide film with aluminum as a major component on a substrate, depositing an amorphous oxide semiconductor film on the first metal oxide film under an oxygen partial pressure of 3% to 5%, processing the oxide semiconductor film into a patterned oxide semiconductor layer, crystallizing the oxide semiconductor layer by performing a first heat treatment on the patterned oxide semiconductor layer, processing the first metal oxide film using the crystallized oxide semiconductor layer as a mask, depositing a gate insulating film on the oxide semiconductor layer, and forming a gate electrode on the gate insulating film, wherein a thickness of the oxide semiconductor film is more than 10 nm and 30 nm or less.

Abstract: A semiconductor device according to an embodiment includes: a substrate; a metal oxide layer arranged above the substrate and having aluminum as the main component of the metal oxide layer; an oxide semiconductor layer arranged above the metal oxide layer; a gate electrode facing the oxide semiconductor layer; and a gate insulating layer between the oxide semiconductor layer and the gate electrode, wherein a thickness of the metal oxide layer is 1 nm or more and 4 nm or less.

Abstract: A display device includes a display panel including a display portion having a plurality of pixels; and a sensor element disposed on a rear side of the display portion. The display portion has a first region overlapping the sensor element and a second region other than the first region in a plan view. Each of the plurality of pixels has a semiconductor device including a channel portion and a conductive portion made of an oxide semiconductor having a polycrystalline structure. Each of the plurality of pixels in the first region is connected by a first signal line comprising the same layer as the conductive portion, and each of the plurality of pixels in the second region is connected by a second signal line comprising a metal layer connected to the conductive portion.

Abstract: A semiconductor device includes a oxide semiconductor layer provided on an insulating surface and having a channel area, a source area and a drain area sandwiching the channel area, a gate electrode opposite the channel area, and a gate insulating layer provided between the oxide semiconductor layer and the gate electrode, wherein the gate electrode is an oxide conductive layer having the same composition as the oxide semiconductor layer, and the oxide conductive layer includes the same impurity element as the source area and the drain area.

Abstract: A semiconductor device includes an oxide semiconductor layer having a polycrystalline structure on an insulating surface, a gate electrode over the oxide semiconductor layer, and a gate insulating layer between the oxide semiconductor layer and the gate electrode. The oxide semiconductor layer includes a first region having a first crystal structure overlapping the gate electrode and a second region having a second crystal structure not overlapping the gate electrode. An electrical conductivity of the second region is larger than an electrical conductivity of the first region. The second crystal structure is identical to the first crystal structure.

Abstract: A semiconductor device including: an oxide semiconductor layer including a first surface and a second surface opposite to the first surface; a gate electrode facing the oxide semiconductor layer; a gate insulating layer between the oxide semiconductor layer and the gate electrode; and a pair of first electrode being in contact with the first surface of the oxide semiconductor layer, respectively, wherein the oxide semiconductor layer including a region in which composition ratio of nitrogen is 2 percent or more within a depth range of 2 nanometers from the first surface in a region vicinity of an edge of at least one of the first electrode of the pair of first electrode.

Abstract: A method for manufacturing semiconductor device according to an embodiment includes; forming an oxide semiconductor layer above a substrate; forming a gate insulating layer above the oxide semiconductor layer; forming a metal oxide layer containing aluminum as a main component above the gate insulating layer; performing a heat treatment in a state where the metal oxide layer is formed above the gate insulating layer; removing the metal oxide layer after the heat treatment; and forming a gate electrode above the gate insulating layer.

Abstract: A method for manufacturing semiconductor device according to an embodiment includes: forming a first metal oxide layer containing aluminum as a main component above a substrate; forming an oxide semiconductor layer above the first metal oxide layer; forming a gate insulating layer above the oxide semiconductor layer; forming a second metal oxide layer containing aluminum as a main component above the gate insulating layer; performing a heat treatment in a state where the second metal oxide layer is formed above the gate insulating layer; removing the second metal oxide layer after the heat treatment; and forming a gate electrode above the gate insulating layer.

Abstract: A display device includes a light-emitting element; a first transistor and a second transistor connected in series between the light-emitting element and a driving power line; a third transistor electrically connected to a gate electrode of the first transistor; and a fourth transistor connected in parallel between a drain electrode of the first transistor and the light-emitting element, wherein a ratio of a channel width W1 to a channel length L1 of the first transistor (a W1/L1 ratio) and a ratio of a channel width W2 to a channel length L2 of the second transistor (a W2/L2 ratio) are larger than a ratio of a channel width W3 to a channel length L3 of the third transistor (a W3/L3 ratio) and a ratio of a channel width W4 to a channel length L4 of the fourth transistor (a W4/L4 ratio).

Abstract: According to one embodiment, a semiconductor device includes a semiconductor layer including a source area, a drain area and a channel area, a first insulating layer, an etching stopper layer located immediately above the channel area and being thinner than the first insulating layer, a second insulating layer provided on the etching stopper layer and being thicker than the first insulating layer, a gate electrode, a third insulating layer which covers the etching stopper layer, the second insulating layer and the gate electrode and covers the first insulating layer immediately above the source area and immediately above the drain area, a source electrode in contact with the source area, and a drain electrode in contact with the drain area.

Abstract: According to one embodiment, a method of manufacturing a semiconductor device, includes forming a first insulating layer, an oxide semiconductor layer, a second insulating layer, a buffer layer and a metal layer sequentially on a base, forming a patterned resist on the metal layer, etching the buffer layer and the metal layer using the resist as a mask to expose an upper surface of the second insulating layer, reducing a volume of the resist to expose an upper surface along a side surface of the metal layer, etching the metal layer using the resist as a mask, to form a gate electrode and to expose an upper surface of the buffer layer, and carrying out ion implantation on the oxide semiconductor layer using the gate electrode as a mask.

Abstract: According to one embodiment, a method of manufacturing a semiconductor device comprises forming an oxide semiconductor layer, forming a gate insulating layer in contact with the oxide semiconductor layer and covering the oxide semiconductor layer, and forming a gate electrode on the gate insulating layer so as to overlap the oxide semiconductor layer, and injecting boron through the gate electrode and the gate insulating layer after forming the gate electrode, wherein a boron concentration included in a region of the gate insulating layer overlapping the gate electrode is in a range of 1E+16 [atoms/cm3] or more.