Abstract: It is an object to manufacture a highly reliable display device using a thin film transistor having favorable electric characteristics and high reliability as a switching element. In a bottom gate thin film transistor including an amorphous oxide semiconductor, an oxide conductive layer having a crystal region is formed between an oxide semiconductor layer which has been dehydrated or dehydrogenated by heat treatment and each of a source electrode layer and a drain electrode layer which are formed using a metal material. Accordingly, contact resistance between the oxide semiconductor layer and each of the source electrode layer and the drain electrode layer can be reduced; thus, a thin film transistor having favorable electric characteristics and a highly reliable display device using the thin film transistor can be provided.

Abstract: According to one embodiment, a method of manufacturing a semiconductor device, includes forming a first insulating layer, an oxide semiconductor layer, a second insulating layer, a buffer layer and a metal layer sequentially on a base, forming a patterned resist on the metal layer, etching the buffer layer and the metal layer using the resist as a mask to expose an upper surface of the second insulating layer, reducing a volume of the resist to expose an upper surface along a side surface of the metal layer, etching the metal layer using the resist as a mask, to form a gate electrode and to expose an upper surface of the buffer layer, and carrying out ion implantation on the oxide semiconductor layer using the gate electrode as a mask.

Abstract: An object is to provide a display device with excellent display characteristics, where a pixel circuit and a driver circuit provided over one substrate are formed using transistors which have different structures corresponding to characteristics of the respective circuits. The driver circuit portion includes a driver circuit transistor in which a gate electrode layer, a source electrode layer, and a drain electrode layer are formed using a metal film, and a channel layer is formed using an oxide semiconductor. The pixel portion includes a pixel transistor in which a gate electrode layer, a source electrode layer, and a drain electrode layer are formed using an oxide conductor, and a semiconductor layer is formed using an oxide semiconductor. The pixel transistor is formed using a light-transmitting material, and thus, a display device with higher aperture ratio can be manufactured.

Abstract: A display device including a pixel having a memory. The pixel includes at least a display element, a capacitor, an inverter, and a switch. The switch is controlled with a signal held in the capacitor and a signal output from the inverter so that voltage is supplied to the display element. The inverter and the switch can be constituted by transistors with the same polarity. A semiconductor layer included in the pixel may be formed using a light-transmitting material. Moreover, a gate electrode, a drain electrode, and a capacitor electrode may be formed using a light-transmitting conductive layer. The pixel is formed using a light-transmitting material in such a manner, whereby the display device can be a transmissive display device while including a pixel having a memory.

Abstract: A display device includes a plurality of pixel electrodes each connected to a semiconductor device, a plurality of common electrodes each disposed opposite to a part of the plurality of pixel electrodes, and a plurality of common wirings each connected to the plurality of common electrodes. The semiconductor device includes an oxide semiconductor layer having a polycrystalline structure, and at least a part of each common wiring is composed of the oxide semiconductor layer. Each common electrode may be located across a plurality of pixel electrodes.

Abstract: The purpose of the present invention is to suppress a variation in a threshold voltage (? Vth) in a Thin Film Transistor (TFT) using an oxide semiconductor. The present invention takes a structure as follows to attain this purpose. A semiconductor device having TFT using an oxide semiconductor including: a channel region, a source region, a drain region, and a transition region between the channel region and the source region and between the channel region and the drain region, in which a resistivity of the transition region is smaller than that of the channel region, and larger than that of the source region or the drain region; a source electrode is formed overlapping the source region, and a drain electrode is formed overlapping the drain region; and a thickness of the transition region of the oxide semiconductor is larger than a thickness of the channel region of the oxide semiconductor.

Abstract: It is an object to manufacture a highly reliable display device using a thin film transistor having favorable electric characteristics and high reliability as a switching element. In a bottom gate thin film transistor including an amorphous oxide semiconductor, an oxide conductive layer having a crystal region is formed between an oxide semiconductor layer which has been dehydrated or dehydrogenated by heat treatment and each of a source electrode layer and a drain electrode layer which are formed using a metal material. Accordingly, contact resistance between the oxide semiconductor layer and each of the source electrode layer and the drain electrode layer can be reduced; thus, a thin film transistor having favorable electric characteristics and a highly reliable display device using the thin film transistor can be provided.

Abstract: A semiconductor device comprises a first insulating layer; an oxide semiconductor layer having a polycrystalline structure on the first insulating layer; a gate insulating layer on the semiconductor oxide layer; a buffer layer on the gate insulating layer; a gate wiring on the buffer layer; and a second insulating layer on the gate wiring. The oxide semiconductor layer has a first region, a second region and a third region aligned toward a first direction. An electrical resistivity of the second region is higher than an electrical resistivity of the first region and lower than an electrical resistivity of the third region. A sheet resistance of the third region is less than 1000 ohm/square.

Abstract: A semiconductor device according to an embodiment of the present invention includes an oxide semiconductor layer having a polycrystalline structure and including an impurity region containing an impurity element, a gate electrode over the oxide semiconductor layer, an insulating layer between the oxide semiconductor layer and the gate electrode, a first contact hole penetrating the insulating layer and exposing the impurity region, a second contact hole penetrating at least the insulating layer and having a greater depth than the first contact hole, and a connection wiring electrically connecting the impurity region to a layer which is exposed in the second contact hole through the first contact hole and the second contact hole. The connection wiring includes a first conductive layer and a second conductive layer on the first conductive layer. A portion of the first conductive layer that is exposed from the second conductive layer contains the impurity element.

Abstract: A semiconductor device includes a gate electrode, an oxide semiconductor layer having a polycrystalline structure, and a gate insulating layer between the gate electrode and the oxide semiconductor layer. The oxide semiconductor layer includes a source region and a drain region each containing an impurity element, a channel region between the source region and the drain region, and a first region adjacent to the channel region. The first region includes a first edge extending along a first direction travelling from the source region to the drain region. The first region has a higher electrical resistivity than each of the source region and the drain region. An etching rate of the oxide semiconductor layer is less than 3 nm/min when the oxide semiconductor layer is etched using an etching solution containing phosphoric acid as a main component at 40° C.

Abstract: A semiconductor device according to an embodiment of the present invention includes: a first semiconductor layer; a first gate electrode; a first gate insulating layer; a first insulating layer above the first gate electrode; a first electrode overlapping the first semiconductor layer, and electrically connected to the first semiconductor layer; a second semiconductor layer above the first insulating layer and made of a different material from the first semiconductor layer; a second gate electrode; a second gate insulating layer; a second electrode overlapping the second semiconductor layer, and electrically connected to the second semiconductor layer; and a first metal nitride layer between the second semiconductor layer and the second electrode, wherein the second semiconductor layer is polycrystalline, and an etching rate of the second semiconductor layer with respect to an etchant including phosphoric acid as a main component is less than 3 nm/min at 40° C.

Abstract: A semiconductor device includes a light shielding layer, a first silicon nitride insulating layer in contact with the light shielding layer with a first interface, a first silicon oxide insulating layer in contact with the first silicon nitride layer with a second interface, and an oxide semiconductor layer over the first silicon oxide insulating layer. The first silicon oxide insulating layer is in contact with the second silicon oxide insulating layer. A thickness t of the first silicon nitride layer satisfies a condition in which light reflected at the first interface and light reflected at the second interface weaken each other when light having a wavelength of 450 nm is incident on the first silicon nitride insulating layer at an angle of 60 degrees from a normal direction of the second interface.

Abstract: A semiconductor device according to an embodiment of the present invention includes: an oxide semiconductor layer; a first gate electrode facing the oxide semiconductor layer; a first gate insulating layer between the oxide semiconductor layer and the first gate electrode; an electrode arranged in a region overlapping the oxide semiconductor layer in a plan view and electrically connected to the oxide semiconductor layer; and a metal nitride layer between the oxide semiconductor layer and the electrode, wherein the oxide semiconductor layer is polycrystalline, and an etching rate of the oxide semiconductor layer with respect to an etchant containing phosphoric acid as a main component is less than 3 nm/min at 40° C.

Abstract: A radiation detector according to an embodiment of the present invention includes: a transistor in which an oxide semiconductor layer is used in a channel of the transistor; a photoelectric converting layer connected to the transistor; a wavelength converting layer facing the photoelectric converting layer and capable of emitting visible light based on radioactive rays absorbed by the wavelength converting layer; and an oxide layer in contact with the oxide semiconductor layer between the transistor and the photoelectric converting layer, wherein a thickness of the oxide layer is 50 nm or less.

Abstract: A semiconductor device includes a first gate electrode, an oxide semiconductor layer including a first oxide semiconductor having a polycrystalline structure over the first gate electrode, a source electrode and a drain electrode electrically connected to the oxide semiconductor layer, and a second gate electrode overlapping the first gate electrode and the oxide semiconductor layer over the source electrode and the drain electrode. In a plan view, the second gate electrode is located with a space from each of the source electrode and the drain electrode. The second gate electrode is electrically connected to the first gate electrode.

Abstract: A display device includes a light-emitting element, a first transistor, and a second transistor, the first transistor includes a first gate electrode, a first insulating film, a first oxide semiconductor layer, a second insulating film, and a first conductive layer provided on the second insulating film, and the second transistor includes the first insulating film, a second oxide semiconductor layer, a second insulating film, and a second gate electrode, wherein an etching rate of the first oxide semiconductor layer and the second semiconductor layer is less than 3 nm/min when the first oxide semiconductor layer and the second semiconductor layer are etched using an etching solution containing phosphoric acid as a main component at 40° C.

Abstract: A logic circuit includes a thin film transistor having a channel formation region formed using an oxide semiconductor, and a capacitor having terminals one of which is brought into a floating state by turning off the thin film transistor. The oxide semiconductor has a hydrogen concentration of 5×1019 (atoms/cm3) or less and thus substantially serves as an insulator in a state where an electric field is not generated. Therefore, off-state current of a thin film transistor can be reduced, leading to suppressing the leakage of electric charge stored in a capacitor, through the thin film transistor. Accordingly, a malfunction of the logic circuit can be prevented. Further, the excessive amount of current which flows in the logic circuit can be reduced through the reduction of off-state current of the thin film transistor, resulting in low power consumption of the logic circuit.

Abstract: A semiconductor device includes a metal oxide layer containing aluminum as a main component above an insulating surface, an oxide semiconductor layer on the metal oxide layer; a gate electrode facing the oxide semiconductor layer, and a gate insulating layer between the oxide semiconductor layer and the gate electrode, wherein a water contact angle on an upper surface of the metal oxide layer is 20° or lower.

Abstract: A display device having a plurality of pixels arranged in a matrix along a first direction and a second direction intersecting the first direction, each of the plurality of pixels includes, a transistor including an oxide semiconductor layer, a gate wiring extending in the first direction opposite the oxide semiconductor layer, and a gate insulating layer between the oxide semiconductor layer and the gate wiring, a first conductive layer provided on at least one first insulating layer above the transistor and in contact with the oxide semiconductor layer, a second insulating layer provided on the first conductive layer, a first inorganic layer provided on the second insulating layer and having openings therein, and a second inorganic layer provided on the first inorganic layer and in contact with the second insulating layer in the opening.

Abstract: A thin film transistor includes an oxide semiconductor layer having a polycrystalline structure over a substrate, a gate electrode over the oxide semiconductor layer, and a gate insulating layer between the oxide semiconductor layer and the gate electrode. The oxide semiconductor layer includes a first region having a first carrier concentration and overlapping the gate electrode, a second region having a second carrier concentration and not overlapping the gate electrode, and a third region between the first region and the second region and overlapping the gate electrode. The second carrier concentration is larger than the first carrier concentration. A carrier concentration of the third region decreases from the second region to the first region in a channel length direction. A length of the third region is greater than or equal to 0.00 ?m and less than or equal to 0.60 ?m in the channel length direction.