Abstract: A manufacture process of a thin film transistor mounted on an EL display device is simplified. A thin film transistor is manufactured by stacking a first conductive film, an insulating film, a semiconductor film, an impurity semiconductor film, and a second conductive film; forming a first resist mask over the stacked films; performing first etching to form a thin-film stack body; performing second etching by side etching is conducted on the thin-film stack body to form a gate electrode layer; and forming a source and drain electrode layer and the like with use of a second resist mask. An EL display device is manufactured using the thin film transistor.

Abstract: To provide a semiconductor device and a display device which can be manufactured through a simplified process and the manufacturing technique. Another object is to provide a technique by which a pattern of wirings or the like which is partially constitutes a semiconductor device or a display device can be formed with a desired shape with controllability.

Abstract: An object of the invention is to provide a method for manufacturing semiconductor devices that are flexible in which elements fabricated using a comparatively low-temperature (less than 500° C.) process are separated from a substrate. After a molybdenum film is formed over a glass substrate, a molybdenum oxide film is formed over the molybdenum film, a nonmetal inorganic film and an organic compound film are stacked over the molybdenum oxide film, and elements fabricated by a comparatively low-temperature (less than 500° C.) process are formed using existing manufacturing equipment for large glass substrates, the elements are separated from the glass substrate.

Abstract: A method for manufacturing a thin film transistor having high electric characteristics with high productivity. In the method for forming a channel region of a dual-gate thin film transistor including a first gate electrode and a second gate electrode which faces the first gate electrode with the channel region provided therebetween, a first microcrystalline semiconductor film is formed under a first condition for forming a microcrystalline semiconductor film in which a space between crystal grains is filled with an amorphous semiconductor, and a second microcrystalline semiconductor film is formed over the first microcrystalline semiconductor film under a second condition for promoting crystal growth.

Abstract: A manufacturing method of a thin film transistor and a display device using a small number of masks is provided. A first conductive film, an insulating film, a semiconductor film, an impurity semiconductor film, and a second conductive film are stacked. Then, a resist mask having a recessed portion is formed thereover using a multi-tone mask. First etching is performed to form a thin-film stack body, and second etching in which the thin-film stack body is side-etched is performed to form a gate electrode layer. The resist is made to recede, and then, a source electrode, a drain electrode, and the like are formed; accordingly, a thin film transistor is manufactured.

Abstract: The invention provides a display device and a method for manufacturing thereof by increasing a material efficiently as well as simplifying steps. Also, the invention provides a technique for forming a pattern such as a wiring, that is used for forming a display device, to have a predetermined shape with an excellent controllability. The method for manufacturing a display device includes the steps of: forming a lyophobic region; selectively irradiating laser beam in the lyophobic region to form a lyophilic region; selectively discharging a composition, that contains a conductive material, in the lyophilic region to form a gate electrode layer; forming a gate insulating layer and a semiconductor layer over the gate electrode layer; discharging a composition containing a conductive material over the semiconductor layer to form a source electrode layer and a drain electrode layer; and forming a pixel electrode layer on the source or drain electrode layer.

Abstract: An object of the invention is to provide a method for manufacturing semiconductor devices that are flexible in which elements fabricated using a comparatively low-temperature (less than 500° C.) process are separated from a substrate. After a molybdenum film is formed over a glass substrate, a molybdenum oxide film is formed over the molybdenum film, a nonmetal inorganic film and an organic compound film are stacked over the molybdenum oxide film, and elements fabricated by a comparatively low-temperature (less than 500° C.) process are formed using existing manufacturing equipment for large glass substrates, the elements are separated from the glass substrate.

Abstract: Disclosed is a thin film transistor including: a gate insulating layer covering a gate electrode; a microcrystalline semiconductor region over the gate insulating layer; a pair of amorphous semiconductor region over the microcrystalline semiconductor; a pair of impurity semiconductor layers over the amorphous semiconductor regions; and wirings over the impurity semiconductor layers. The microcrystalline semiconductor region has a surface having a projection and depression on the gate insulating layer side. The microcrystalline semiconductor region includes a first microcrystalline semiconductor region which is not covered with the amorphous regions and a second microcrystalline semiconductor region which is in contact with the amorphous semiconductor regions. A thickness d1 of the first microcrystalline semiconductor region is smaller than a thickness d2 of the second microcrystalline semiconductor region and d1 is greater than or equal to 30 nm.

Abstract: An object is to provide a display device whose frame can be narrowed and whose display characteristics are excellent. The display device includes a driver circuit and a pixel portion. The driver circuit and the pixel portion are formed using a dual-gate thin film transistor and a single-gate thin film transistor, respectively. In the dual-gate thin film transistor in the display device, a semiconductor layer is formed using a microcrystalline semiconductor region and a pair of amorphous semiconductor regions, and a gate insulating layer and an insulating layer are in contact with the microcrystalline semiconductor region of the semiconductor layer.

Abstract: The invention provides a display device and a method for manufacturing thereof by increasing a material efficiently as well as simplifying steps. Also, the invention provides a technique for forming a pattern such as a wiring, that is used for forming a display device, to have a predetermined shape with an excellent controllability. The method for manufacturing a display device includes the steps of: forming a lyophobic region; selectively irradiating laser beam in the lyophobic region to form a lyophilic region; selectively discharging a composition, that contains a conductive material, in the lyophilic region to form a gate electrode layer; forming a gate insulating layer and a semiconductor layer over the gate electrode layer; discharging a composition containing a conductive material over the semiconductor layer to form a source electrode layer and a drain electrode layer; and forming a pixel electrode layer on the source or drain electrode layer.

Abstract: In a manufacturing process of a semiconductor device, electroplating and CMP have had a problem of increase in manufacturing costs for forming a wiring. Correspondingly, an opening is formed in a porous insulating film after a mask is formed thereover, and a conductive material containing Ag is dropped into the opening. Further, a first conductive layer is formed by baking the conductive material dropped into the opening by selective irradiation with laser light. Subsequently, a metal film is formed over the entire surface by sputtering, and the mask is removed thereafter to have only the metal film remain over the first conductive layer, thereby forming an embedded wiring layer formed with a stack of the first conductive layer containing Ag and the second conductive layer (metal film).

Abstract: An object is to provide a thin film transistor with small off current, large on current, and high field-effect mobility. A silicon nitride layer and a silicon oxide layer which is formed by oxidizing the silicon nitride layer are stacked as a gate insulating layer, and crystals grow from an interface of the silicon oxide layer of the gate insulating layer to form a microcrystalline semiconductor layer; thus, an inverted staggered thin film transistor is manufactured. Since crystals grow from the gate insulating layer, the thin film transistor can have a high crystallinity, large on current, and high field-effect mobility. In addition, a buffer layer is provided to reduce off current.

Abstract: A method for manufacturing a semiconductor device having flexibility by separating an element that is manufactured by a comparatively low-temperature (temperature of less than 500° C.) process from a substrate is provided. The element is separated from a glass substrate by the following steps: forming a silicone layer over a glass substrate; performing plasma treatment to the surface of the silicone layer to weaken the surface of the silicone layer; stacking an organic compound layer over the silicone layer; and forming an element that is manufactured through a process at a comparatively low-temperature, typically, a temperature that the organic compound can withstand, over the compound layer.

Abstract: A display device including a thin film transistor with high electric characteristics and high reliability, and a method for manufacturing the display device with high mass-productivity. In a display device including an inverted-staggered channel-stop-type thin film transistor, the inverted-staggered channel-stop-type thin film transistor includes a microcrystalline semiconductor film including a channel formation region, and an impurity region containing an impurity element of one conductivity type is selectively provided in a region which is not overlapped with source and drain electrodes, in the channel formation region of the microcrystalline semiconductor film.

Abstract: A display device including a thin film transistor with high electric characteristics and high reliability, and a method for manufacturing the display device with high mass-productivity. In a display device including an inverted-staggered channel-stop-type thin film transistor, the inverted-staggered channel-stop-type thin film transistor includes a microcrystalline semiconductor film including a channel formation region, and an impurity region containing an impurity element of one conductivity type is selectively provided in a region which is not overlapped with source and drain electrodes, in the channel formation region of the microcrystalline semiconductor film.

Abstract: Off current of a bottom gate thin film transistor in which a semiconductor layer is shielded from light by a gate electrode is reduced. A thin film transistor includes a gate electrode layer; a first semiconductor layer; a second semiconductor layer, provided on and in contact with the first semiconductor layer; a gate insulating layer between and in contact with the gate electrode layer and the first semiconductor layer; impurity semiconductor layers in contact with the second semiconductor layer; and source and drain electrode layers partially in contact with the impurity semiconductor layers and the first and second semiconductor layers. The entire surface of the first semiconductor layer on the gate electrode layer side is covered by the gate electrode layer; and a potential barrier at a portion where the first semiconductor layer is in contact with the source or drain electrode layer is 0.5 eV or more.

Abstract: In a manufacturing process of a semiconductor device, electroplating and CMP have had a problem of increase in manufacturing costs for forming a wiring. Correspondingly, an opening is formed in a porous insulating film after a mask is formed thereover, and a conductive material containing Ag is dropped into the opening. Further, a first conductive layer is formed by baking the conductive material dropped into the opening by selective irradiation with laser light. Subsequently, a metal film is formed over the entire surface by sputtering, and the mask is removed thereafter to have only the metal film remain over the first conductive layer, thereby forming an embedded wiring layer formed with a stack of the first conductive layer containing Ag and the second conductive layer (metal film).

Abstract: Conductive layers having knots are adjacently formed with uniform distance therebetween. Droplets of the conductive layers are discharged to stagger centers of the droplets in a length direction of wirings so that the centers of the discharged droplets are not on the same line in a line width direction between the adjacent conductive layers. Since the centers of the droplets are staggered, parts of the conductive layers each having a widest line width (the widest width of knot) are not connected to each other, and the conductive layers can be formed adjacently with a shorter distance therebetween.

Abstract: A thin film transistor includes, over a substrate having an insulating surface, a gate insulating layer covering a gate electrode; a semiconductor layer which includes a plurality of crystalline regions in an amorphous structure and which forms a channel formation region, in contact with the gate insulating layer; a semiconductor layer including an impurity element imparting one conductivity type, which forms source and drain regions; and a buffer layer including an amorphous semiconductor between the semiconductor layer and the semiconductor layer including an impurity element imparting one conductivity type. The crystalline regions have an inverted conical or inverted pyramidal crystal particle which grows approximately radially in a direction in which the semiconductor layer is deposited, from a position away from an interface between the gate insulating layer and the semiconductor layer.

Abstract: In a manufacturing process of a semiconductor device, electroplating and CMP have had a problem of increase in manufacturing costs for forming a wiring. Correspondingly, an opening is formed in a porous insulating film after a mask is formed thereover, and a conductive material containing Ag is dropped into the opening. Further, a first conductive layer is formed by baking the conductive material dropped into the opening by selective irradiation with laser light. Subsequently, a metal film is formed over the entire surface by sputtering, and the mask is removed thereafter to have only the metal film remain over the first conductive layer, thereby forming an embedded wiring layer formed with a stack of the first conductive layer containing Ag and the second conductive layer (metal film).