Abstract: In a semiconductor circuit in a display device, there are provided a first gate electrode of a first MOS transistor formed on a semiconductor layer via a gate insulating film, a second gate electrode of a second MOS transistor formed on the semiconductor layer via the gate insulating film at a distance from the first gate electrode, first and second one conductivity type impurity introduced regions formed in the semiconductor layer on both sides of the first gate electrode to serve as source/drain of the first MOS transistor, and first and second opposite conductivity type impurity introduced regions formed in the semiconductor layer on both sides of the second gate electrode to serve as source/drain of the second MOS transistor. One of the first and second opposite conductivity type impurity introduced regions is formed to contact mutually to the second one conductivity type impurity introduced region.

Abstract: A TFT formed on an insulating substrate source, drain and channel regions, a gate insulating film formed on at least the channel region and a gate electrode formed on the gate insulating film. Between the channel region and the drain region, a region having a higher resistivity is provided in order to reduce an Ioff current. A method for forming this structure comprises the steps of anodizing the gate electrode to form a porous anodic oxide film on the side of the gate electrode; removing a portion of the gate insulating using the porous anodic oxide film as a mask so that the gate insulating film extends beyond the gate electrode but does not completely cover the source and drain regions. Thereafter, an ion doping of one conductivity element is performed. The high resistivity region is defined under the gate insulating film.

Abstract: The present invention provides an active matrix type display device having a high aperture ratio and a required auxiliary capacitor. A source line and a gate line are overlapped with part of a pixel electrode. This overlapped region functions to be a black matrix. Further, an electrode pattern made of the same material as the pixel electrode is disposed to form the auxiliary capacitor by utilizing the pixel electrode. It allows a required value of auxiliary capacitor to be obtained without dropping the aperture ratio. Also, it allows the electrode pattern to function as a electrically shielding film for suppressing the cross-talk between the source and gate lines and the pixel electrode.

Abstract: An auxiliary capacitor for a pixel of an active matrix type liquid crystal display is provided without decreasing the aperture ratio. A transparent conductive film for a common electrode is formed under a pixel electrode constituted by a transparent conductive film with an insulation film provided therebetween. Further, the transparent conductive film for the common electrode is maintained at fixed potential, formed so as to cover a gate bus line and a source bus line, and configured such that signals on each bus line are not applied to the pixel electrode. The pixel electrode is disposed so that all edges thereof overlap the gate bus line and source bus line. As a result, each of the bus lines serves as a black matrix. Further, the pixel electrode overlaps the transparent conductive film for the common electrode to form a storage capacitor.

Abstract: An auxiliary capacitor for a pixel of an active matrix type liquid crystal display is provided without decreasing the aperture ratio. A transparent conductive film for a common electrode is formed under a pixel electrode constituted by a transparent conductive film with an insulation film provided therebetween. Further, the transparent conductive film for the common electrode is maintained at fixed potential, formed so as to cover a gate bus line and a source bus line, and configured such that signals on each bus line are not applied to the pixel electrode. The pixel electrode is disposed so that all edges thereof overlap the gate bus line and source bus line. As a result, each of the bus lines serves as a black matrix. Further, the pixel electrode overlaps the transparent conductive film for the common electrode to form a storage capacitor.

Abstract: A TFT formed on an insulating substrate source, drain and channel regions, a gate insulating film formed on at least the channel region and a gate electrode formed on the gate insulating film. Between the channel region and the drain region, a region having a higher resistivity is provided in order to reduce an Ioff current. A method for forming this structure comprises the steps of anodizing the gate electrode to form a porous anodic oxide film on the side of the gate electrode; removing a portion of the gate insulating using the porous anodic oxide film as a mask so that the gate insulating film extends beyond the gate electrode but does not completely cover the source and drain regions. Thereafter, an ion doping of one conductivity element is performed. The high resistivity region is defined under the gate insulating film.

Abstract: There is provided a method by which lightly doped drain (LDD) regions can be formed easily and at good yields in source/drain regions in thin film transistors possessing gate electrodes covered with an oxide covering. A lightly doped drain (LDD) region is formed by introducing an impurity into an island-shaped silicon film in a self-aligning manner, with a gate electrode serving as a mask. First, low-concentration impurity regions are formed in the island-shaped silicon film by using rotation-tilt ion implantation to effect ion doping from an oblique direction relative to the substrate. Low-concentration impurity regions are also formed below the gate electrode at this time. After that, an impurity at a high concentration is introduced normally to the substrate, so forming high-concentration impurity regions. In the above process, a low-concentration impurity region remains below the gate electrode and constitutes a lightly doped drain region.

Abstract: A low temperature process for fabricating a high-performance and reliable semiconductor device in high yield, comprising forming a silicon oxide film as a gate insulator by chemical vapor deposition using TEOS as a starting material under an oxygen, ozone, or a nitrogen oxide atmosphere on a semiconductor coating having provided on an insulator substrate; and irradiating a pulsed laser beam or an intense light thereto to remove clusters of such as carbon and hydrocarbon to thereby eliminate trap centers from the silicon oxide film. Also claimed is a process comprising implanting nitrogen ions into a silicon oxide film and annealing the film thereafter using an infrared light, to thereby obtain a silicon oxynitride film as a gate insulator having a densified film structure, a high dielectric constant, and an improved-withstand voltage.

Abstract: A metal electrode also serving as a black matrix is so formed as to cover the periphery of an IT0 pixel electrode. A region where the pixel electrode and the metal electrode coextend also serves as an auxiliary capacitor. Since the auxiliary capacitor can be formed by using a thin insulating film, it can have a large capacitance. By virtue of the structure in which the black matrix also serves as the auxiliary capacitor, it is not necessary to provide an electrode dedicated to the auxiliary capacitor, thereby preventing reduction in aperture ratio. Further, the black matrix can completely shield a source line and a gate line from light.

Abstract: An LDD structure is manufactured to have a desired aspect ratio of the height to the width of a gate electrode. The gate electrode is first deposited on a semiconductor substrate followed by ion implantation with the gate electrode as a mask to form a pair of impurity regions. The gate electrode is then anodic oxidized to form an oxide film enclosing the electrode. With the oxide film as a mask, highly doped regions are formed by ion implantation in order to define lightly doped regions between the highly doped regions and the channel region located therebetween.

Abstract: A process for manufacturing a semiconductor device, particularly a thin film transistor, by using a crystalline silicon film having excellent characteristics. The process comprises forming a silicon nitride film and an amorphous silicon film in contact thereto, introducing a catalyst element capable of promoting the crystallization of the amorphous silicon film by heating the amorphous silicon film, thereby crystallizing at least a part of the amorphous silicon film, and accelerating the crystallization by irradiating the silicon film with a laser beam or intense light equivalent thereto.

Abstract: In a thin film transistor (TFT), a mask is formed on a gate electrode, and a porous anodic oxide is formed in both sides of the gate electrode using a relatively low voltage. A barrier anodic oxide is formed between the gate electrode and the porous anodic oxide and on the gate electrode using a relatively high voltage. A gate insulating film is etched using the barrier anodic oxide as a mask. The porous anodic oxide is selectively etched after etching barrier anodic oxide, to obtain a region of an active layer on which the gate insulating film is formed and the other region of the active layer on which the gate insulating film is not formed. An element including at least one of oxygen, nitrogen and carbon is introduced into the region of the active layer at high concentration in comparison with a concentration of the other region of the active layer. Further, N- or P-type impurity is introduced into the active layer.

Abstract: A semiconductor material and a method for forming the same, said semiconductor material having produced by a process comprising melting a noncrystal semiconductor film containing therein carbon, nitrogen, and oxygen each at a concentration of 5×1019 atoms·cm?3 or lower, preferably 1×1019 atoms·cm?3 or lower, by irradiating a laser beam or a high intensity light equivalent to a laser beam to said noncrystal semiconductor film, and then recrystallizing the thus molten amorphous silicon film. The present invention provides thin film semiconductors having high mobility at an excellent reproducibility, said semiconductor materials being useful for fabricating thin film semiconductor devices such as thin film transistors improved in device characteristics.

Abstract: A channel forming region of a thin-film transistor is covered with an electrode and wiring line that extends from a source line. As a result, the channel forming region is prevented from being illuminated with light coming from above the thin-film transistor, whereby the characteristics of the thin-film transistor can be made stable.

Abstract: Nickel is introduced to a predetermined region of a peripheral circuit section, other than a picture element section, on an amorphous silicon film to crystallize from that region. After forming gate electrodes and others, sources, drains and channels are formed by doping impurities, and laser is irradiated to improve the crystallization. After that, electrodes/wires are formed. Thereby an active matrix type liquid crystal display whose thin film transistors (TFT) in the peripheral circuit section are composed of the crystalline silicon film whose crystal is grown in the direction parallel to the flow of carriers and whose TFTs in the picture element section are composed of the amorphous silicon film can be obtained.

Abstract: In the fabrication of a CMOS-TFT, non-selectively doping (for both of p- and n-type TFTs) and selectively doping (only for the n-type TFT) with p-type impurities (B: boron) are successively performed at very low concentrations to control the threshold voltages (Vthp and Vthn). More specifically, the Id-Vg characteristics of the p- and n-type TFTs are initially negatively shifted. In this state, non-selectively doping is performed positively to shift the p- and n-type TFTs first to adjust the Vthp to a specified value. Selectively doping is then performed positively to shift only the n-type TFT to adjust the Vthn to a specified value. The threshold voltages of the p- and n-type TFTs constructing the CMOS-TFT can be independently and efficiently (with minimum photolithography) controlled with high accuracy.

Abstract: To provide a thin film transistor having a low OFF characteristic and to provide P-channel type and N-channel type thin film transistors where a difference in characteristics of the P-channel type and the N-channel type thin film transistors is corrected, a region 145 having a P-type behavior more potential than that of a drain region 146 is arranged between a channel forming region 134 and the drain region 146 in the P-channel type thin film transistor whereby the P-channel type thin film transistor having the low OFF characteristic can be provided and a low concentration impurity region 136 is arranged between a channel forming region 137 and a drain region 127 in the N-channel type thin film transistor whereby the N-channel type thin film transistor having the low OFF characteristic and where deterioration is restrained can be provided.

Abstract: A TFT formed on an insulating substrate source, drain and channel regions, a gate insulating film formed on at least the channel region and a gate electrode formed on the gate insulating film. Between the channel region and the drain region, a region having a higher resistivity is provided in order to reduce an Ioff current. A method for forming this structure comprises the steps of anodizing the gate electrode to form a porous anodic oxide film on the side of the gate electrode; removing a portion of the gate insulating using the porous anodic oxide film as a mask so that the gate insulating film extends beyond the gate electrode but does not completely cover the source and drain regions. Thereafter, an ion doping of one conductivity element is performed. The high resistivity region is defined under the gate insulating film.

Abstract: A display device using a novel semiconductor device, which includes a pixel matrix, an image sensor, and a peripheral circuit for driving those, that is, which has both a camera function and a display function, and is made intelligent, is provided and a method of manufacturing the same is also provided. One pixel includes a semiconductor device for display and a semiconductor for light reception, that is, one pixel includes semiconductor devices (insulated gate-type field effect semiconductor device) for controlling both display and light reception, so that the display device having a picture reading function is made miniaturized and compact.

Abstract: [Purpose] It is an object to obtain a crystalline silicon film having preferable characteristics for a thin film transistor. [Structure] A crystalline silicon film having improved crystallinity is obtained by the following steps: forming a silicon nitride film substantially in contact with an amorphous silicon film on glass substrate; introducing a catalyst element such as nickel; performing an annealing treatment at a temperature of 500 to 600° C. for crystallization; and further irradiating it with a laser light, thereby a crystalline silicon film having improved crystallinity can be obtained. By using the crystalline silicon film thus obtained, a semiconductor device such as a TFT having improved characteristic can be obtained.