To improve field-effect mobility and reliability of a transistor including an oxide semiconductor film. Provided is a semiconductor device including an oxide semiconductor film. The semiconductor device includes a first insulating film, the oxide semiconductor film over the first insulating film, a second insulating film and a third insulating film over the oxide semiconductor film, and a gate electrode over the second insulating film. The oxide semiconductor film includes a first oxide semiconductor film, a second oxide semiconductor film over the first oxide semiconductor film, and a third oxide semiconductor film over the second oxide semiconductor film. The first to third oxide semiconductor films contain the same element. The second oxide semiconductor film includes a region where the crystallinity is lower than the crystallinity of one or both of the first oxide semiconductor film and the third oxide semiconductor film.

Disclosed are a method and a device for manufacturing an array substrate, and an array substrate. The method includes: depositing and forming a gate insulation layer on a pre-formed base substrate and a pre-formed gate, the gate insulation layer covering the pre-formed gate; depositing and forming an amorphous silicon layer, a doped amorphous silicon layer including at least three doped layers, and a metal layer on the gate insulation layer in sequence, doping concentrations of the at least three doped layers of the doped amorphous silicon layer increasing from bottom to top; etching patterns of the amorphous silicon layer, the doped amorphous silicon layer and the metal layer to form the array substrate.

A method for making an array substrate includes the following steps: forming a poly-silicon semiconductor layer on a substrate; forming a buffer layer on the substrate; depositing a first metal layer, and patterning the first metal layer to form gate electrodes for a driving TFT, a switch TFT, and a poly-silicon TFT; forming a first gate insulator layer; forming a second gate insulator layer; defining through holes passing through the buffer layer, the first gate insulator layer, and the second gate insulator layer to expose the poly-silicon semiconductor layer; depositing a metal oxide layer to form a first metal oxide semiconductor layer; and depositing a second metal layer to form source electrodes and drain electrodes for the driving TFT, the switch TFT, and the poly-silicon TFT.

A method for forming a transistor structure includes steps as follows: A substrate with an original surface is prepared. Next a gate conductive region is formed, wherein at least a portion of the gate conductive region is disposed below the original surface, and a bottom wall and sidewalls of the gate conductive region is surrounded by a gate dielectric layer. Then, a first conductive region is formed, wherein a bottom wall of the first conductive region is aligned or substantially aligned with a top wall of the gate conductive region.

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 high 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 active device substrate includes a substrate, a first semiconductor layer, a gate insulating layer, a first gate, a first source, a first drain and a shielding electrode. The first semiconductor layer includes a first heavily doped region, a first lightly doped region, a channel region, a second lightly doped region, and a second heavily doped region that are sequentially connected. The first gate is located on the gate insulating layer and overlaps the channel region. The first source is electrically connected to the first heavily doped region. The first drain is electrically connected to the second heavily doped region. The shielding electrode overlaps the second lightly doped region in a normal direction of the substrate.

The present disclosure provides a thin film transistor and a fabrication method thereof, an array substrate and a fabrication method thereof, and a display panel. The method for fabricating a thin film transistor includes: forming an active layer including a first region, a second region and a third region on a substrate; forming a gate insulating layer on a side of the active layer away from the substrate; forming a gate electrode on a side of the gate insulating layer away from the active layer; and ion-implanting the active layer from a side of the gate electrode away from the active layer, so that the first region is formed into a heavily doped region, the second region is formed into a lightly doped region, and the third region is formed into an active region.

A thin film transistor according to an exemplary embodiment of the present invention includes an oxide semiconductor. A source electrode and a drain electrode face each other. The source electrode and the drain electrode are positioned at two opposite sides, respectively, of the oxide semiconductor. A low conductive region is positioned between the source electrode or the drain electrode and the oxide semiconductor. An insulating layer is positioned on the oxide semiconductor and the low conductive region. A gate electrode is positioned on the insulating layer. The insulating layer covers the oxide semiconductor and the low conductive region. A carrier concentration of the low conductive region is lower than a carrier concentration of the source electrode or the drain electrode.

An electro-optical device includes a scanning line extending along a first direction and having a light shielding property, a transistor having a semiconductor layer extending along the first direction so as to overlap with the scanning line, a contact hole electrically coupled to the scanning line at a side of a channel region of the semiconductor layer, and an opening provided at a side of a first LDD region and a second LDD region of the semiconductor layer.

A thin film transistor includes an active layer, first and second electrodes, and a third doped pattern. The active layer has a channel region, and a first electrode region and a second electrode region, the first electrode region has a first ion doping concentration, and the second electrode region has a second ion doping concentration. The first electrode and the second electrode are disposed on a side of the active layer in the thickness direction. The first electrode is coupled to the first electrode region, and the second electrode is coupled to the second electrode region. The third doped pattern is disposed between the first electrode and the first electrode region, and in direct contact with the first electrode and the first electrode region. The third doped pattern has a third ion doping concentration, and the third ion doping concentration is different from the first ion doping concentration.