Abstract: In a process for manufacturing a thin film transistor having a semiconductor layer constituting source and drain regions and a channel forming region, by the semiconductor layer being made thinner in the source and drain regions than in the channel forming region a structure is realized wherein, at the boundary between the source region and the channel forming region and the boundary between the drain region and the channel forming region, portions where electric field concentrations occur are displaced from the portion where a channel is formed. By reducing the OFF current (the leak current) without also reducing the ON current, a high mutual conductance is realized.

Abstract: In a producing a thin film transistor, a solution containing a metal element for promoting crystallization of silicon is added in contact with an amorphous silicon film, and then a silicide layer is formed by heating process. Further, after a region as crystal growth nucleus is formed by patterning the silicide layer, laser light is irradiated while heating process. As a result, crystal-growth is performed from the region as crystal growth nucleus in the amorphous silicon film, thereby to form monodomain regions corresponding to a single crystal. Also, before the solution is added, the amorphous silicon film may be subjected to plasma treatment 30.

Abstract: A preparing method of a semiconductor, particularly a preparing method of a polycrystal semiconductor film which has a good electrical property is disclosed. In order to obtain a non-crystalline silicon film containing a lot of combination of hydrogen and silicon, a forming process of a non-crystalline silicon film by a low temperature gas phase chemical reaction, a process of a heat annealing to produce a lot of dangling bonds of silicon, so as to draw out hydrogen from said non-crystalline silicon film, and a process of applying a laser irradiation to said non-crystal silicon film having a lot of dangling bond of silicon are conducted.

Abstract: There is provided an improvement on homogeneity of annealing performed utilizing radiation of a laser beam on a silicon film having a large area. In a configuration wherein a linear laser beam is applied to a surface to be irradiated, optimization is carried out on the width and number of cylindrical lenses forming homogenizers 103 and 104 for controlling the distribution of radiation energy density in the longitudinal direction of the linear beam. For example, the width of the cylindrical lenses forming the homogenizers 103 and 104 is set in the range from 0.1 mm to 5 mm, and the number of the lenses is chosen such that one lens is provided for every 5 mm-15 mm along the length of the linear laser beam in the longitudinal direction thereof. This makes it possible to improve homogeneity of the radiation energy density of the linear laser in the longitudinal direction thereof.

Abstract: In the substrate treatment apparatus including substrate treatment chambers (301 and 303) and a buffer chamber (302) having an exhaust system (306b) independent of the substrate treatment chambers, connection tubes (304a and 304b) are provided between the substrate treatment chambers and the buffer chamber, and gas inlets are respectively provided for the connection tubes. A gas (308) for treating a substrate flows from the connection tube (304a) into the substrate treatment chamber (301) and the buffer chamber (302), while a gas (309) for treating a substrate flows from the connection tube (304b) into the substrate treatment chamber (303) and the buffer chamber (302). Accordingly, the gas does not move from the substrate treatment chamber to the buffer chamber against a gas flow, thereby allowing the separation between ambiences.

Abstract: In producing a semiconductor device by annealing with laser light irradiation, while a linear laser light is scanned in a direction perpendicular to a line, the annealing is performed for a semiconductor material. In this state, since an anneal effect in a beam lateral direction corresponding to a line direction is 2 times or more different than that in the scanning direction, a plurality of semiconductor elements are formed along a line direction in which the linear laser light is irradiated. Also, a line direction connecting the source and drain region of a thin film transistor is aligned to the line direction of the linear laser light.

Abstract: A laser-irradiation method which comprises a process for fabricating a semiconductor device, comprising: a first step of forming a thin film amorphous semiconductor on a substrate having an insulating surface; a second step of modifying the thin film amorphous semiconductor into a crystalline thin film semiconductor by irradiating a pulse-type linear light and/or by applying a heat treatment; a third step of implanting an impurity element which imparts a one conductive type to the crystalline thin film semiconductor; and a fourth step of activating the impurity element by irradiating a pulse-type linear light and/or by applying a heat treatment; wherein the peak value, the peak width at half height, and the threshold width of the laser energy in the second and the fourth steps above are each distributed within a range of approximately ±3% of the standard value. Also claimed is a laser irradiation device which realizes the method above.

Abstract: In order to promote an effect of laser annealing in respect of a semiconductor film, moisture is intentionally included in an atmosphere in irradiating laser beam to the semiconductor film by which a temperature holding layer comprising water vapor is formed on the surface of the semiconductor film in irradiating the laser beam and the laser annealing operation can be performed effectively.

Abstract: In crystallizing an amorphous silicon film by illuminating it with linear pulse laser beams having a normal-distribution type beam profile or a similar beam profile, the linear pulse laser beams are applied in an overlapped manner. There can be obtained effects similar to those as obtained by a method in which the laser illumination power is gradually increased and then decreased in a step-like manner in plural scans.

Abstract: In producing a thin film transistor, after an amorphous silicon film is formed on a substrate, a nickel silicide layer is formed by spin coating with a solution (nickel acetate solution) containing nickel as the metal element which accelerates (promotes) the crystallization of silicon and by heat treating. The nickel silicide layer is selectively patterned to form island-like nickel silicide layer. The amorphous silicon film is patterned. A laser light is irradiated while moving the laser, so that crystal growth occurs from the region in which the nickel silicide layer is formed and a region equivalent to a single crystal (a monodomain region) is obtained.

Abstract: There is provided an improvement on homogeneity of annealing performed utilizing radiation of a laser beam on a silicon film having a large area. In a configuration wherein a linear laser beam is applied to a surface to be irradiated, optimization is carried out on the width and number of cylindrical lenses forming homogenizers 103 and 104 for controlling the distribution of radiation energy density in the longitudinal direction of the linear beam. For example, the width of the cylindrical lenses forming the homogenizers 103 and 104 is set in the range from 0.1 mm to 5 mm, and the number of the lenses is chosen such that one lens is provided for every 5 mm-15 mm along the length of the linear laser beam in the longitudinal direction thereof. This makes it possible to improve homogeneity of the radiation energy density of the linear laser in the longitudinal direction thereof.

Abstract: A laser-irradiation method which comprises a process for fabricating a semiconductor device, comprising:

Abstract: A preparing method of a semiconductor, particularly a preparing method of a polycrystal semiconductor film which has a good electrical property is disclosed. In order to obtain a non-crystalline silicon film containing a lot of combination of hydrogen and silicon, a forming process of a non-crystalline silicon film by a low temperature gas phase chemical reaction, a process of a heat annealing to produce a lot of dangling bonds of silicon, so as to draw out hydrogen from said non-crystalline silicon film, and a process of applying a laser irradiation to said non-crystal silicon film having a lot of dangling bond of silicon are conducted.

Abstract: A semiconductor material and a method for forming the same, said semiconductor material having fabricated by a process comprising irradiating a laser beam or a high intensity light equivalent to a laser beam to an amorphous silicon 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, without melting the amorphous silicon film. The present invention provides thin film semiconductors having high mobility at an excellent reproducibility, said semiconductor materials being useful for fabricating compact thin film semiconductor devices such as thin film transistors improved in device characteristics.

Abstract: Laser annealing is performed by irradiating, while scanning, a semiconductor thin-film with laser light. The laser light that is linear on the irradiation surface is moved in its line-width direction and applied non-continuously. The laser light has, in its line-width direction, an energy density profile that assumes a step-like form in which the energy density varies in a step-like manner. In particular, the scanning pitch D and the step widths Ln are so set as to satisfy a relationship Ln≧D.

Abstract: A laser-annealing method includes the steps of a first step of cleaning a non-monocrystal silicon film formed on a substrate, and a second step of laser-annealing the non-monocrystal silicon film in an atmosphere containing oxygen therein, wherein the first and second steps are conducted continuously without being exposed to the air. Also, a laser-annealing device includes a cleaning chamber, and a laser irradiation chamber, wherein a substrate to be processed is transported between the cleaning chamber and the laser irradiation chamber without being exposed to the air.

Abstract: An object of the present invention is to provide a TFT with which better characteristics can be obtained using a good crystalline silicon film. An amorphous semiconductor film having a thickness of 400 Å or more is formed on an insulating surface, is crystallized by heat annealing or photo annealing or the combined use thereof, and is wholly or selectively etched to form a region having a thickness of 300 Å or less. This is used as a channel-forming region in a TFT.

Abstract: A linear pulse laser beam to be applied to an illumination surface is so formed as to have, at the focus, an energy profile in the width direction which satisfies inequalities 0.5L1≦L2≦L1 and 0.5L1≦L3≦L1 where assuming that a maximum energy is 1, L1 is a beam width of two points having an energy of 0.95 and L1+L2+L3 is a beam width of two points having an energy of 0.70, L2 and L3 occupying two peripheral portions of the beam width. According to another aspect of the invention, a compound-eye-like fly-eye lens for expanding a pulse laser beam in a sectional manner is provided upstream of a cylindrical lens for converging the laser beam into a linear beam.

Abstract: In order to promote an effect of laser annealing in respect of a semiconductor film, moisture is intentionally included in an atmosphere in irradiating laser beam to the semiconductor film by which a temperature holding layer comprising water vapor is formed on the surface of the semiconductor film in irradiating the laser beam and the laser annealing operation can be performed effectively.

Abstract: A linear pulse laser beam to be applied to an illumination surface is so formed as to have, at the focus, an energy profile in the width direction which satisfies inequalities 0.5L1≦L2≦L1 and 0.5L1≦L3≦L1 where assuming that a maximum energy is 1, L1 is a beam width of two points having an energy of 0.95 and L1+L2+L3 is a beam width of two points having an energy of 0.70, L2 and L3 occupying two peripheral portions of the beam width. According to another aspect of the invention, a compound-eye-like fly-eye lens for expanding a pulse laser beam in a sectional manner is provided upstream of a cylindrical lens for converging the laser beam into a linear beam.