A novel display apparatus is provided. The display apparatus includes a first layer and a second layer over the first layer. The first layer includes a functional circuit. The second layer includes a display unit including a plurality of pixels and a memory unit including a plurality of memory cells. Each of the plurality of pixels includes a pixel circuit and a light-emitting element over the pixel circuit. The functional circuit includes a display unit driver circuit and a control circuit. The memory unit has a function of storing image data that is to be output through the display unit driver circuit to the display unit. The memory cell includes a first transistor for retaining a potential corresponding to the image data, and a second transistor for reading the potential. The first transistor is provided in the second layer, and the second transistor is provided in the first layer.

A display apparatus that is less affected by noise is provided. The display apparatus includes a signal line driver circuit, a demultiplexer circuit, and a pixel. The demultiplexer circuit includes a transistor in which a semiconductor layer is provided in an opening formed in an interlayer insulating layer over a substrate. A first conductive layer provided below the opening is used as one of a source electrode and a drain electrode of the transistor, and a second conductive layer covering a side surface of the opening in a plan view is used as the other of the source electrode and the drain electrode. The first conductive layer is electrically connected to the pixel, and the second conductive layer is electrically connected to the signal line driver circuit.

A semiconductor device including a transistor having a minute size is provided. In the semiconductor device, a second conductive layer is provided over a first conductive layer; the second conductive layer has a first opening overlapping with the first conductive layer; a third conductive layer is provided over the second conductive layer; the third conductive layer has a second opening overlapping with the first opening; a first insulating layer is in contact with a sidewall of the first opening in the second conductive layer; a semiconductor layer is in contact with a top surface of the first conductive layer, a side surface of the first insulating layer, and a top surface of the third conductive layer; a second insulating layer is provided over the semiconductor layer; a fourth conductive layer is provided over the second insulating layer; the first insulating layer includes a region sandwiched between the sidewall of the first opening in the second conductive layer and the semiconductor layer; and the semiconductor layer includes a region sandwiched between the sidewall of the first opening in the second conductive layer and the fourth conductive layer.

A semiconductor device including a transistor having a minute size is provided. In the semiconductor device, a second conductive layer is provided over a first conductive layer; the second conductive layer has a first opening overlapping with the first conductive layer; a third conductive layer is provided over the second conductive layer; the third conductive layer has a second opening overlapping with the first opening; a first insulating layer is in contact with a sidewall of the first opening in the second conductive layer; a semiconductor layer is in contact with a top surface of the first conductive layer, a side surface of the first insulating layer, and a top surface of the third conductive layer; a second insulating layer is provided over the semiconductor layer; a fourth conductive layer is provided over the second insulating layer; the first insulating layer includes a region sandwiched between the sidewall of the first opening in the second conductive layer and the semiconductor layer; and the semiconductor layer includes a region sandwiched between the sidewall of the first opening in the second conductive layer and the fourth conductive layer.

A semiconductor device having a high degree of integration is provided. A first and second transistors which are electrically connected to each other and a first insulating layer are included. The first transistor includes a first semiconductor layer, a second insulating layer, and a first to third conductive layers. The second transistor includes a second semiconductor layer, a third insulating layer, and a fourth to sixth conductive layers. The first insulating layer is positioned over the first conductive layer and includes an opening reaching the first conductive layer. The second conductive layer is positioned over the first insulating layer. The first semiconductor layer is in contact with a top surface of the first conductive layer, an inner wall of the opening, and the second conductive layer. The third conductive layer is positioned over the second insulating layer to overlap with the inner wall of the opening. The third insulating layer is positioned over the fourth conductive layer. The fifth and sixth conductive layers are positioned over the fourth conductive layer with the third insulating layer therebetween. The second semiconductor layer is in contact with top surfaces of the fifth and sixth conductive layers, side surfaces thereof that face each other, and a top surface of the third insulating layer sandwiched between the fifth conductive layer and the sixth conductive layer.

A semiconductor device having a high degree of integration is provided. A first and second transistors which are electrically connected to each other and a first insulating layer are included. The first transistor includes a first semiconductor layer, a second insulating layer, and a first to third conductive layers. The second transistor includes a second semiconductor layer, a third insulating layer, and a fourth to sixth conductive layers. The first insulating layer is positioned over the first conductive layer and includes an opening reaching the first conductive layer. The second conductive layer is positioned over the first insulating layer. The first semiconductor layer is in contact with a top surface of the first conductive layer, an inner wall of the opening, and the second conductive layer. The third conductive layer is positioned over the second insulating layer to overlap with the inner wall of the opening. The third insulating layer is positioned over the fourth conductive layer. The fifth and sixth conductive layers are positioned over the fourth conductive layer with the third insulating layer therebetween. The second semiconductor layer is in contact with top surfaces of the fifth and sixth conductive layers, side surfaces thereof that face each other, and a top surface of the third insulating layer sandwiched between the fifth conductive layer and the sixth conductive layer.

A semiconductor device includes a first power supply line, a second power supply line, a first ground line, a switch circuit connected to the first and the second power supply line, and a switch control circuit connected to the first ground line and the first power supply line. The switch circuit includes a first and a second transistor of a first conductive type. A first gate electrode of the first transistor is connected to a second gate electrode of the second transistor. The switch control circuit includes a third transistor of a second conductive type, and a fourth transistor of a third conductive type. A third gate electrode of the third transistor is connected to a fourth gate electrode of the fourth transistor. A semiconductor device includes a signal line that electrically connects a connection point between the third and fourth transistor to the first and second gate electrode.

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.

Nanosheet transistor devices are provided. A nanosheet transistor device includes a transistor stack that includes a lower nanosheet transistor having a first nanosheet width and a lower gate width. The transistor stack also includes an upper nanosheet transistor that is on the lower nanosheet transistor and that has a second nanosheet width and an upper gate width that are different from the first nanosheet width and the lower gate width, respectively. Related methods of forming a nanosheet transistor device are also provided.

A display device includes a base substrate including a display area and a non-display area around the display area are defined, a first interlayer insulating layer disposed on the base substrate, a second interlayer insulating layer disposed on the first interlayer insulating layer, a first semiconductor layer disposed on the second interlayer insulating layer and including an oxide, and a first gate insulating layer disposed on the first semiconductor layer, wherein the material of the first interlayer insulating layer and the material of the second interlayer insulating layer are different from each other. Methods of manufacturing a display device are also disclosed.