An object is to provide a semiconductor device having a structure with which parasitic capacitance between wirings can be sufficiently reduced. An oxide insulating layer serving as a channel protective layer is formed over part of an oxide semiconductor layer overlapping with a gate electrode layer. In the same step as formation of the oxide insulating layer, an oxide insulating layer covering a peripheral portion of the oxide semiconductor layer is formed. The oxide insulating layer which covers the peripheral portion of the oxide semiconductor layer is provided to increase the distance between the gate electrode layer and a wiring layer formed above or in the periphery of the gate electrode layer, whereby parasitic capacitance is reduced.

A semiconductor device includes: a first electrode; a second electrode; a first oxide semiconductor layer provided between the first electrode and the second electrode; a gate electrode around the first oxide semiconductor layer; a second oxide semiconductor layer provided between the gate electrode and the first oxide semiconductor layer, and separated from the first electrode; and a gate insulating layer provided between the gate electrode and the second oxide semiconductor layer.

A display substrate and a display device are provided. The display substrate includes a base and subpixels. The subpixel includes: a data line pattern; a power source signal line pattern including a portion extending in the first direction; and a subpixel driving circuitry. The subpixel driving circuitry includes two switching transistors, a driving transistor, and a storage capacitor. First and second electrode plates of the storage capacitor are coupled to a gate electrode of the driving transistor and the power source signal line pattern respectively. Second electrodes of the two switching transistors are coupled to a first electrode of the driving transistor. An orthogonal projection of the second electrode of at least one of the switching transistors onto the base at least partially overlaps an orthogonal projection of the power source signal line pattern onto the base, and at least partially overlaps an orthogonal projection of the second electrode plate of the storage capacitor onto the base.

A substrate includes a base material having an insulating property, a pixel electrode provided on one surface side of the base material, a pixel transistor provided between the base material and the pixel electrode, a first reflective film provided between the pixel transistor and the pixel electrode, and a common electrode provided between the pixel transistor and the first reflective film. The first reflective film has a first through-hole, the common electrode has a second through-hole, and a drain of the pixel transistor is coupled to the pixel electrode through the first through-hole and the second through-hole.

Transistor structures with a channel semiconductor material that is passivated with two-dimensional (2D) crystalline material. The 2D material may comprise a semiconductor having a bandgap offset from a band of the channel semiconductor. The 2D material may be a thin as a few monolayers and have good temperature stability. The 2D material may be a conversion product of a sacrificial precursor material, or of a portion of the channel semiconductor material. The 2D material may comprise one or more metal and a chalcogen. The channel material may be a metal oxide semiconductor suitable for low temperature processing (e.g., IGZO), and the 2D material may also be compatible with low temperature processing (e.g., <450° C.). The 2D material may be a chalcogenide of a metal present in the channel material (e.g., ZnS.sub.x or ZnSe.sub.x) or of a metal absent from the channel material when formed from a sacrificial precursor.

A device includes a gate electrode and a gate dielectric surrounding the gate electrode. The gate electrode surrounds a nanostructure. The nanostructure includes stacked nanosheets. The gate dielectric is formed by a high-k (HK) material. The HK material covers sidewalls of the gate electrode in a direction aligned to adjacent devices. Portions of the HK material are recessed from the sidewalls and refilled by a dielectric material with a dielectric constant less than the HK material and an electrical isolation capability greater than the HK material. Replacing the HK material over the sidewalls of the gate electrode with the dielectric material enhances electrical isolation between the gate electrode with adjacent contacts. Consequently, it can reduce electrical leakage between metal gate (MG) contacts and metal-to-device (MD) contacts in scaled transistors of an integrated circuit (IC).

An object of an embodiment of the present invention is to manufacture a semiconductor device with high display quality and high reliability, which includes a pixel portion and a driver circuit portion capable of high-speed operation over one substrate, using transistors having favorable electric characteristics and high reliability as switching elements. Two kinds of transistors, in each of which an oxide semiconductor layer including a crystalline region on one surface side is used as an active layer, are formed in a driver circuit portion and a pixel portion. Electric characteristics of the transistors can be selected by choosing the position of the gate electrode layer which determines the position of the channel. Thus, a semiconductor device including a driver circuit portion capable of high-speed operation and a pixel portion over one substrate can be manufactured.

Integrated circuit (IC) including transistors with high-mobility/high-saturation velocity, non-silicon channel materials coupled to a silicon substrate through counter-doped sub-channel materials, which greatly reduce electrical leakage currents through the substrate when the IC is operated at very low temperatures (e.g., below −25 C). With low temperature operation, high transistor performance associated with the non-silicon channel materials can be integrated into high density IC architectures that avoid the limitations associated with semiconductor material layer transfers.

An object of an embodiment of the present invention is to manufacture a semiconductor device with high display quality and high reliability, which includes a pixel portion and a driver circuit portion capable of high-speed operation over one substrate, using transistors having favorable electric characteristics and high reliability as switching elements. Two kinds of transistors, in each of which an oxide semiconductor layer including a crystalline region on one surface side is used as an active layer, are formed in a driver circuit portion and a pixel portion. Electric characteristics of the transistors can be selected by choosing the position of the gate electrode layer which determines the position of the channel. Thus, a semiconductor device including a driver circuit portion capable of high-speed operation and a pixel portion over one substrate can be manufactured.

To reduce power consumption and suppress display degradation of a liquid crystal display device. To suppress display degradation due to an external factor such as temperature. A transistor whose channel formation region is formed using an oxide semiconductor layer is used for a transistor provided in each pixel. Note that with the use of a high-purity oxide semiconductor layer, off-state current of the transistor at a room temperature can be 10 aA/μm or less and off-state current at 85° C. can be 100 aA/μm or less. Consequently, power consumption of a liquid crystal display device can be reduced and display degradation can be suppressed. Further, as described above, off-state current of the transistor at a temperature as high as 85° C. can be 100 aA/μm or less. Thus, display degradation of a liquid crystal display device due to an external factor such as temperature can be suppressed.