An array substrate includes a pixel circuit and a light-emitting diode. The pixel circuit includes a driving transistor including a first active medium made of polysilicon, and a switching transistor including a second active medium made of polysilicon. The first active medium has a first grain size. The second active medium has a second grain size larger than the first grain size. The light-emitting diode is coupled to the pixel circuit.

A laser irradiation apparatus (1) according to an embodiment includes an optical-system module (20) configured to apply laser light (L1) to an object to be irradiated, a shield plate (51) in which a slit (54) is formed, through which the laser light (L1) passes, and a reflected-light receiving component (61) disposed between the optical-system module (20) and the shield plate (51), in which the reflected-light receiving component (61) is able to receive, out of the laser light (L1), reflected light (R1) reflected by the shield plate (51).

An oxide thin film transistor, an array substrate, and preparation methods thereof are disclosed. The method for preparing an oxide thin film transistor comprises a step of forming a pattern comprising an oxide semiconductor active layer on a substrate, wherein the step comprises: forming an amorphous oxide semiconductor thin film on the substrate; performing an excimer laser annealing, at least at a position in the amorphous oxide semiconductor thin film corresponding to a channel region of oxide semiconductor active layer to be formed, such that the amorphous oxide semiconductor material at the laser-annealed position is crystallized, to form a crystalline oxide semiconductor material; and forming the pattern comprising the oxide semiconductor active layer.

An active matrix substrate (100) according to an embodiment of the present invention has a display region (DR) defined by a plurality of pixel regions (P) arranged in a matrix pattern, and a peripheral region (FR) located around the display region. The active matrix substrate includes a substrate (1), a first TFT (10) supported on the substrate and including a crystalline silicon semiconductor layer (11), and a second TFT (20) supported on the substrate and including an oxide semiconductor layer (21). The first TFT and the second TFT each have a top gate structure. The oxide semiconductor layer is located below the crystalline silicon semiconductor layer.

A laser annealing method includes: step A of providing a substrate having an amorphous semiconductor film formed on a surface thereof; and step B of selectively irradiating a portion of the amorphous semiconductor film with laser light. The step B includes a step of simultaneously forming, in the portion, two molten regions that have elongate shapes congruent to each other and are arranged in line symmetry with each other.

There is provided a technique that enables a reduction in the display failure of a display device and the improvement of the yields of the display device in a display device that adopts a semiconductor device including a thin film transistor using an oxide semiconductor. A semiconductor device according to an embodiment includes a thin film transistor having an oxide semiconductor. The oxide semiconductor has a drain region, a source region, and a channel region provided between the drain region and the source region. The thin film transistor includes a gate insulating film provided on the channel region, an aluminum oxide film provided on the gate insulating film, an insulating film provided on the aluminum oxide film, and a gate electrode provided on the insulating film.

A transistor comprises a top source/drain region, a bottom source/drain region, a channel region vertically between the top and bottom source/drain regions, and a gate operatively laterally-adjacent the channel region. At least one of the top source/drain region, the bottom source/drain region, and the channel region are crystalline. All crystal grains within the at least one of the top source/drain region, the bottom source/drain region, and the channel region have average crystal sizes within 0.064 m.sup.3 of one another. Other embodiments, including methods, are disclosed.

A display device includes: a plurality of pixels connected to gate lines and data lines; a gate driver to supply a gate signal to the gate lines; and a data driver to supply a data signal to the data lines. The gate driver includes: a first transistor including a first active layer at a first layer; and a second transistor including a second active layer at a second layer on the first layer.

The present invention is characterized in that by laser beam being slantly incident to the convex lens, an aberration such as astigmatism or the like is occurred, and the shape of the laser beam is made linear on the irradiation surface or in its neighborhood. Since the present invention has a very simple configuration, the optical adjustment is easier, and the device becomes compact in size. Furthermore, since the beam is slantly incident with respect to the irradiated body, the return beam can be prevented.

A method for manufacturing a display substrate is provided to include: forming an amorphous silicon layer on a base substrate; irradiating at least part of the display region through a mask plate with a laser, to convert a portion of the amorphous silicon layer in the irradiated part of the display region corresponding to channel regions of active layers of transistors into polycrystalline silicon by a laser annealing process; irradiating at least part of the peripheral region with a laser, to convert the amorphous silicon layer in the irradiated part of the peripheral region into polycrystalline silicon; and forming the active layers of the transistors from the amorphous silicon layer which is converted to polycrystalline silicon by a patterning process.