A light-emitting device capable of suppressing variation in luminance among pixels is provided. A light-emitting device includes a pixel and first and second circuits. The first circuit has a function of generating a signal including a value of current extracted from the pixel. The second circuit has a function of correcting an image signal by the signal. The pixel includes at least a light-emitting element and first and second transistors. The first transistor has a function of controlling supply of the current to the light-emitting element by the image signal. The second transistor has a function of controlling extraction of the current from the pixel. A semiconductor film of each of the first and second transistors includes a first semiconductor region overlapping with a gate, a second semiconductor region in contact with a source or a drain, and a third semiconductor region between the first and second semiconductor regions.

It is an object to provide a semiconductor device which can supply a signal with sufficient amplitude to a scan line while power consumption is kept small. Further, it is an object to provide a semiconductor device which can suppress distortion of a signal supplied to the scan line and shorten a rising time and a falling time while power consumption is kept small. A semiconductor device which includes a plurality of pixels each including a display element and at least one first transistor and a scan line driver circuit supplying a signal for selecting the plurality of pixels to a scan line. A light-transmitting conductive layer is used for a pixel electrode layer of the display element, a gate electrode layer of the first transistor, source and drain electrode layers of the first transistor, and the scan line. The scan line driver circuit includes a second transistor and a capacitor for holding a voltage between a gate electrode layer of the second transistor and a source electrode layer of the second transistor. The source electrode of the second transistor is connected to the scan line.

Provided is a thin film transistor including an active layer including a first silicon active layer, a second silicon active layer, and an oxide active layer in a space between the first silicon active layer and the second silicon active layer, a gate electrode on the active layer with a gate insulating layer disposed therebetween, and a source electrode and a drain electrode with an interlayer insulating layer disposed between the gate electrode and the source and drain electrodes, the source and drain electrodes being in contact with the first silicon active layer and the second silicon active layer, respectively.

An organic light emitting display includes a pixel circuit to supply current to an organic light emitting device. The pixel circuit includes a switching transistor and a driving transistor. The switching transistor includes a first insulating layer between a first gate electrode and an oxide semiconductor layer. The driving transistor includes a second gate electrode on an active layer. The first insulating layer is between the active layer and the second gate electrode.

An array substrate includes a substrate, driving TFTs, and switch TFTs directly on the substrate. The driving TFT includes a buffer layer, a gate, a first gate insulator layer, a second gate insulator layer, and a metal oxide semiconductor layer stacked in that order on the substrate, and a source electrode and a drain electrode coupled to the metal oxide semiconductor layer. The switch TFT includes a buffer layer, a gate, a second gate insulator layer, and a metal oxide semiconductor layer stacked in that order on the substrate, and a source electrode and a drain electrode coupled to the metal oxide semiconductor layer.

A semiconductor device provided with a plurality of kinds of transistors with different device structures suitable for functions of circuits is provided. The semiconductor device includes first to third transistors with different device structures over one substrate. A semiconductor layer of the first transistor is an oxide semiconductor film with a stacked-layer structure, and a semiconductor layer of each of the second and third transistors is an oxide semiconductor film with a single-layer structure. Each of the first and second transistors includes a back gate electrode connected to its gate electrode.

Provided is a semiconductor device including a first transistor having an oxide semiconductor film, an interlayer film over the first transistor, and second transistor located over the interlayer film and having a semiconductor film including silicon. The interlayer film can include an inorganic insulator. The semiconductor film including silicon can contain polycrystalline silicon. The interlayer film can include an inorganic insulator.

A pixel driver circuit having only three conductive layers is described. The pixel driver circuit comprises a vertical driver transistor (26) spanning said three conductive layers, wherein a first of said conductive layers (22) on a first side of a middle conductive layer (32) provides a first source-drain connection (52) of said driver transistor, wherein a third of said conductive layers (34) on the opposite side of said middle conductive layer to said first conductive layer provides a gate connection (54) for said vertical driver transistor, and wherein said middle conductive layer provides a second source-drain connection (50) for said vertical driver transistor. The circuit also comprises a lateral switching transistor (30) with source-drain connections (44,46) in one of said three conductive layers. A dielectric layer (16, 20) is provided between said first and second conductive layers and between said second and third conductive layers, and wherein semiconductor material (18) is provided spanning said first and second source-drain connections of said vertical driver transistor. A pixel display element (12) is coupled to said first source-drain connection of said vertical driver transistor.

A semiconductor device (1001) includes: a first transistor (10A) having a first channel length L1 and a first channel width W1; and a second transistor (10B) having a second channel length L2 and a second channel width W2, wherein the first transistor (10A) and the second transistor (10B) include an active layer formed from a common oxide semiconductor film, the first transistor (10A) is a memory transistor which is capable of being irreversibly changed from a semiconductor state where a drain current Isd depends on a gate voltage Vg to a resistor state where the drain current Isd does not depend on the gate voltage Vg, and the first channel length L1 is smaller than the second channel length L2.

There is provided a flexible display having a plurality of innovations configured to allow bending of a portion or portions to reduce apparent border size and/or utilize the side surface of an assembled flexible display.