A semiconductor device includes thin film transistors each having an oxide semiconductor. The oxide semiconductor has a channel region, a drain region, a source region, and low concentration regions which are lower in impurity concentration than the drain region and the source region. The low concentration regions are located between the channel region and the drain region, and between the channel region and the source region. Each of the thin film transistors has a gate insulating film on the channel region and the low concentration regions, an aluminum oxide film on a first part of the gate insulating film, the first part being located on the channel region, and a gate electrode on the aluminum oxide film and a second part of the gate insulating film, the second part being located on the low concentration regions.

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.

An object is to shorten the time for rewriting data in memory cells. A memory module includes a first memory cell, a second memory cell, a selection transistor, and a wiring WBL1. The first memory cell includes a first memory node. The second memory cell includes a second memory node. One end of the first memory cell is electrically connected to the wiring WBL1 through the selection transistor. The other end of the first memory cell is electrically connected to one end of the second memory cell. The other end of the second memory cell is electrically connected to the wiring WBL1. When the selection transistor is on, data in the first memory node is rewritten by a signal supplied through the selection transistor to the wiring WBL1. When the selection transistor is off, data in the first memory node is rewritten by a signal supplied through the second memory node to the wiring WBL1.

A semiconductor device with favorable electrical characteristics is provided. A semiconductor device with stable electrical characteristics is provided. A highly reliable display device is provided. The semiconductor device is fabricated by a method that includes a first step of forming a semiconductor layer containing a metal oxide, a second step of forming a conductive film over the semiconductor layer, a third step of etching the conductive film such that the conductive film is divided over the semiconductor layer and a portion of the semiconductor layer is uncovered, and a fourth step of performing first treatment on the conductive film and the portion of the semiconductor layer. The conductive film contains copper, silver, gold, or aluminum. The first treatment is plasma treatment in an atmosphere containing a mixed gas of a first gas containing an oxygen element and a second gas containing a hydrogen element.

A display device that is suitable for increasing in size is achieved. Three or more source lines are provided for each pixel column. Video signals having the same polarity are input to adjacent source lines during one frame period. Dot inversion driving is used to reduce a flicker, crosstalk, or the like.

To provide a semiconductor device with favorable electrical characteristics. To provide a method for manufacturing a semiconductor device with high productivity. To reduce the temperatures in a manufacturing process of a semiconductor device. An island-like oxide semiconductor layer is formed over a first insulating film; a second insulating film and a first conductive film are formed in this order, covering the oxide semiconductor layer; oxygen is supplied to the second insulating film through the first conductive film; a metal oxide film is formed over the second insulating film in an atmosphere containing oxygen; a first gate electrode is formed by processing the metal oxide film; a third insulating film is formed, covering the first gate electrode and the second insulating film; and first heat treatment is performed. The second insulating film and the third insulating film each include oxide. The highest temperature in the above steps is 340° C. or lower.

A thin film transistor, a manufacturing method thereof, an array substrate, and a display panel are provided. The thin film transistor includes a semiconductor layer, a source and a drain. The semiconductor layer includes an active layer and a superhydrophobic layer. The active layer includes a source contact, a drain contact and a channel portion. The source corresponds to the source contact, and the drain corresponds to the drain contact. The superhydrophobic layer is disposed on a surface of the active layer proximal to the source and the drain. The superhydrophobic layer includes a plurality of multi-level nanostructures protruding from the surface of the active layer, and the superhydrophobic layer at least covers a channel portion of the active layer.

A manufacturing method of TFT substrate and a TFT substrate are provided. The method provides a dual-gate structure symmetrically disposed on both sides of active layer, which prevents TFT threshold voltage from changing and improve TFT conduction state switching; by first manufacturing the active layer before the gate insulating layer to make the insulating layer directly grow on active layer, the contact interface between the gate insulating layer and active layer is improved, leading to further improving TFT conduction state switching. The TFT substrate makes the gate located between the source and the pixel electrode in vertical direction, and the dual-gate is symmetrically disposed on both sides of active layer to prevent TFT threshold voltage from changing and improve TFT conduction state switching, as well as improve the contact interface between the gate insulating layer and active layer, leading to further improving TFT conduction state switching.

A thin film transistor is disclosed. The thin-film transistor includes an active layer (3); a source electrode (1); and a drain electrode (2). The active layer includes an active pattern region (4), the active pattern region including a main body portion (5) and a plurality of protrusion portions (6) on both sides of the main body portion. The protrusion portions are connected to the main body portion.

The invention provides a manufacturing method of the TFT array substrate. Compared to existing 4M process, the invention changes the structural design of the semi-transmissive mask for the photoresist layer for patterning the source/drain metal layer and the semiconductor layer. The edge forms a reduced thickness edge portion, so that the edge of the photoresist layer is thinned, and thereby the width of the photoresist layer is easily reduced in subsequent processes, and the semiconductor layer at the edge of the metal wire structure is easily etched during dry etching, reducing the tailing problem of the active layer at edges of source/drain to achieve finer metal wire structure, and improve optical stability, electrical performance, aperture ratio, reliability, power consumption, and the overall performance of the TFT array substrate. The residual problem of amorphous and heavily doped silicon on source/drain edge in original process is solved or reduced.