Abstract:
A transistor with superior electric characteristics is manufactured. An oxide insulating film is formed over a substrate, an oxide semiconductor film is formed over the oxide insulating film, heat treatment is then conducted at a temperature at which hydrogen contained in the oxide semiconductor film is desorbed and part of oxygen contained in the oxide insulating film is desorbed, then the heated oxide semiconductor film is etched into a predetermined shape to form an island-shaped oxide semiconductor film, a pair of electrodes is formed over the island-shaped oxide semiconductor film, a gate insulating film is formed over the pair of electrodes and the island-shaped oxide semiconductor film, and a gate electrode is formed over the gate insulating film.
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 that is suitable for miniaturization. A method for manufacturing a semiconductor device includes the steps of forming a semiconductor, forming a first conductor over the semiconductor, performing a second process on the first conductor so as to form a conductor according to a first pattern, forming a first insulator over the conductor having the first pattern, forming an opening in the first insulator, performing a third process on the conductor having the first pattern in the opening so as to form a first electrode and a second electrode and to expose the semiconductor, forming a second insulator over the first insulator, an inner wall of the opening, and an exposed portion of the semiconductor, forming a second conductor over the second insulator, and performing a fourth process on the second conductor so as to form a third electrode.
Abstract:
A transistor includes a gate, a source, and a drain, the gate is electrically connected to the source or the drain, a first signal is input to one of the source and the drain, and an oxide semiconductor layer whose carrier concentration is 5×1014/cm3 or less is used for a channel formation layer. A capacitor includes a first electrode and a second electrode, the first electrode is electrically connected to the other of the source and the drain of the transistor, and a second signal which is a clock signal is input to the second electrode. A voltage of the first signal is stepped up or down to obtain a third signal which is output as an output signal through the other of the source and the drain of the transistor.
Abstract:
A highly reliable transistor which includes an oxide semiconductor and has high field-effect mobility and in which a variation in threshold voltage is small is provided. By using the transistor, a high-performance semiconductor device, which has been difficult to realize, is provided. The transistor includes an oxide semiconductor film which contains two or more kinds, preferably three or more kinds of elements selected from indium, tin, zinc, and aluminum. The oxide semiconductor film is formed in a state where a substrate is heated. Further, oxygen is supplied to the oxide semiconductor film with an adjacent insulating film and/or by ion implantation in a manufacturing process of the transistor, so that oxygen deficiency which generates a carrier is reduced as much as possible. In addition, the oxide semiconductor film is highly purified in the manufacturing process of the transistor, so that the concentration of hydrogen is made extremely low.
Abstract:
In a liquid crystal display device including a plurality of pixels in a display portion and configured to performed display in a plurality of frame periods, each of the frame periods includes a writing period and a holding period, and after an image signal is input to each of the plurality of pixels in the writing period, a transistor included in each of the plurality of pixels is turned off and the image signal is held for at least 30 seconds in the holding period. The pixel includes a semiconductor layer including an oxide semiconductor layer, and the oxide semiconductor layer has a carrier concentration of less than 1×1014/cm3.
Abstract translation:在包括显示部分中的多个像素并且被配置为在多个帧周期中进行显示的液晶显示装置中,每个帧周期包括写入周期和保持周期,并且在将图像信号输入到每个 在所述写入周期中的所述多个像素中,包括在所述多个像素中的每一个中的晶体管被截止,并且所述图像信号在所述保持周期中保持至少30秒。 像素包括具有氧化物半导体层的半导体层,氧化物半导体层的载流子浓度小于1×10 14 / cm 3。
Abstract:
In the transistor including a gate electrode and an oxide semiconductor film which are provided to overlap with each other with a gate insulating film provided therebetween and a first electrode and a second electrode which are in contact with the oxide semiconductor film, the second electrode partly surrounds an end portion and side surface portions of the first electrode. In the oxide semiconductor film, a channel region is formed in a region which overlaps with the gate electrode and which is between the first electrode and the second electrode. An end portion of the oxide semiconductor film which continuously extends from end portions of the channel region does not overlap with the gate electrode.
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, leadind 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:
An oxide semiconductor film is formed over a substrate. A sacrifice film is formed to such a thickness that the local maximum of the concentration distribution of an injected substance injected into the oxide semiconductor film in the depth direction of the oxide semiconductor film is located in a region from an interface between the substrate and the oxide semiconductor film to a surface of the oxide semiconductor film. Oxygen ions are injected as the injected substance into the oxide semiconductor film through the sacrifice film at such an acceleration voltage that the local maximum of the concentration distribution of the injected substance in the depth direction of the oxide semiconductor film is located in the region, and then the sacrifice film is removed. Further, a semiconductor device is manufactured using the oxide semiconductor film.