Abstract: An orientation ratio of a crystalline semiconductor film obtained by crystallizing an amorphous semiconductor film is increased, a distortion thereof is suppressed, and a TFT using such a crystalline semiconductor film is provided. At the time of formation of the amorphous semiconductor film (102) or after the formation thereof, a noble gas element, typically, argon is included in the film and crystallization is performed therefor. Thus, an orientation ratio of the semiconductor film (104) can be increased and a distortion present in the semiconductor film (104) after the crystallization is suppressed as compared with that present in the semiconductor film before the crystallization. Then, the noble gas element in the film is removed or reduced by laser light irradiation performed later.

Abstract: An object is to enhance the orientation ratio of a crystalline semiconductor film obtained by crystallizing an amorphous semiconductor film while using as a substrate a less-heat-resistive material such as glass thereby providing a semiconductor device using a crystalline semiconductor film with high quality equivalent to a single crystal. A first crystalline semiconductor film and a second crystalline semiconductor film are formed overlying a substrate, which integrally structure a crystalline semiconductor layer. The first and second crystalline semiconductor films are polycrystalline bodies aggregated with a plurality of crystal grains. However, the crystal grains are aligned toward a (101)-plane orientation at a ratio of 30 percent or greater, preferably 80 percent or greater.

Abstract: A first amorphous semiconductor film is formed on an insulating surface. A catalyst element for promoting crystallization is added thereto. Thereafter, by a first heat treatment in an inert gas, a first crystalline semiconductor film is formed. A barrier layer and a second semiconductor layer are formed on the first crystalline semiconductor film. The second semiconductor layer contains a rare gas element at a concentration of 1×1019 to 2×1022/cm3, preferably 1×1020 to 1×1021/cm3 and oxygen at a concentration of 5×1017 to 1×1021/cm3. Subsequently, by a second treatment in an inert gas, the catalyst element remaining in the first crystalline semiconductor film is moved to the second semiconductor film.

Abstract: Contamination of an interface of respective films constituting a TFT due to an contaminant impurity in a clean room atmosphere becomes a great factor to lower the reliability of the TFT. Besides, when an impurity is added to a crystalline semiconductor film, its crystal structure is broken. By using an apparatus for manufacturing a semiconductor device including a plurality of treatment chambers, a treatment can be made without being exposed to a clean room atmosphere in an interval between respective treatment steps, and it becomes possible to keep the interface of the respective films constituting the TFT clean. Besides, by carrying out crystallization after an impurity is added to an amorphous semiconductor film, the breakdown of the crystal structure of the crystalline semiconductor film is prevented.

Abstract: When a laser beam is irradiated onto a semiconductor film, a steep temperature gradient is produced between a substrate and the semiconductor film. For this reason, the semiconductor film contracts, so that a warp in the film occurs. Therefore, the quality of a resulting crystalline semiconductor film sometimes deteriorates. According to the present invention, it is characterized in that, after laser beam crystallization on the semiconductor film, heat treatment is carried out so as to reduce the warp in the film. Since the substrate contracts by the heat treatment, the warp in the semiconductor film is lessened, so that the physical properties of the semiconductor film can be improved.

Abstract: When a laser beam is irradiated onto a semiconductor film, a steep temperature gradient is produced between a substrate and the semiconductor film. For this reason, the semiconductor film contracts, so that a warp in the film occurs. Therefore, the quality of a resulting crystalline semiconductor film sometimes deteriorates. According to the present invention, it is characterized in that, after laser beam crystallization on the semiconductor film, heat treatment is carried out so as to reduce the warp in the film. Since the substrate contracts by the heat treatment, the warp in the semiconductor film is lessened, so that the physical properties of the semiconductor film can be improved.

Abstract: The orientation ratio of a crystalline semiconductor film obtained by crystallizing an amorphous semiconductor film through heat treatment and irradiation of intense light such as laser light, ultraviolet rays, or infrared rays is enhanced, and a semiconductor device whose active region is formed from the crystalline semiconductor film and a method of manufacturing the semiconductor device are provided. In a semiconductor film containing silicon and germanium as its ingredient and having a crystal structure, the {101} plane reaches 30% or more of all the lattice planes detected by Electron backscatter diffraction.

Abstract: A first amorphous semiconductor film is formed on an insulating surface. A catalyst element for promoting crystallization is added thereto. Thereafter, by a first heat treatment in an inert gas, a first crystalline semiconductor film is formed. A barrier layer and a second semiconductor layer are formed on the first crystalline semiconductor film. The second semiconductor layer contains a rare gas element at a concentration of 1×1019 to 2×1022/cm3, preferably 1×1020 to 1×1021/cm3 and oxygen at a concentration of 5×1017 to 1×1021/cm3. Subsequently, by a second treatment in an inert gas, the catalyst element remaining in the first crystalline semiconductor film is moved to the second semiconductor film.

Abstract: An insulating film 103 for making an under insulating layer 104 is formed on a quartz or semiconductor substrate 100. Recesses 105a to 105d corresponding to recesses 101a to 101d of the substrate 100 are formed on the surface of the insulating film 103. The surface of this insulating film 103 is flattened to form the under insulating layer 104. By this flattening process, the distance L1, L2, . . . , Ln between the recesses 106a, 106b, 106d of the under insulating layer 104 is made 0.3 ?m or more, and the depth of the respective recesses is made 10 nm or less. The root-mean-square surface roughness of the surface of the under insulating film 104 is made 0.3 nm or less. By this, in the recesses 106a, 106b, 106d, it can be avoided to block crystal growth of the semiconductor thin film, and crystal grain boundaries can be substantially disappeared.

Abstract: A technique of using a metal element that has a catalytic action over crystallization of a semiconductor film to obtain a crystalline semiconductor film and then effectively removing the metal element remaining in the film is provided. A first semiconductor film (104) having a crystal structure is formed on a substrate. A barrier layer (105) and a second semiconductor film (106) containing a rare gas element are formed on the first semiconductor film (104). A metal element contained in the first semiconductor film (104) is moved to the second semiconductor film (106) through the barrier layer (105) by heat treatment for gettering.

Abstract: The orientation ratio of a crystalline semiconductor film obtained by crystallizing an amorphous semiconductor film through heat treatment and irradiation of intense light such as laser light, ultraviolet rays, or infrared rays is enhanced, and a semiconductor device whose active region is formed from the crystalline semiconductor film and a method of manufacturing the semiconductor device are provided. In a semiconductor film containing silicon and germanium as its ingredient and having a crystal structure, the {101} plane reaches 30% or more of all the lattice planes detected by Electron backscatter diffraction.

Abstract: An insulating film 103 for making an under insulating layer 104 is formed on a quartz or semiconductor substrate 100. Recesses 105a to 105d corresponding to recesses 101a to 101d of the substrate 100 are formed on the surface of the insulating film 103. The surface of this insulating film 103 is flattened to form the under insulating layer 104. By this flattening process, the distance L1, L2, . . . , Ln between the recesses 106a, 106b, 106d of the under insulating layer 104 is made 0.3 ?m or more, and the depth of the respective recesses is made 10 nm or less. The root-mean-square surface roughness of the surface of the under insulating film 104 is made 0.3 nm or less. By this, in the recesses 106a, 106b, 106d, it can be avoided to block crystal growth of the semiconductor thin film, and crystal grain boundaries can be substantially disappeared.

Abstract: The present invention has as its object to provide a technique of forming a surface of a thin-film semiconductor having corrugations and smoothing the same. This is achieved by a fabrication method for thin-film semiconductors which smooths a surface of a silicon film having corrugations, comprising the steps of forming an oxidized silicon film on the surface of the silicon film, removing the oxidized silicon film which has been formed in protruding portions among the corrugations and exposing at least part of protruding portions in the silicon film, and removing the protrusions in the silicon film exposed in the previous step. In the above structure, the silicon film having corrugations has an average thickness of about 100 ? to 1000 ? (e.g. an amorphous silicon film or a crystalline silicon film crystallized by thermal processing) which is irradiated by a laser beam and crystallized or a silicon layer promoting crystallization.

Abstract: The orientation of a crystalline semiconductor film obtained by crystallizing an amorphous semiconductor film is improved and a TFT formed from this crystalline semiconductor film is provided. In a semiconductor device whose TFT is formed from a semiconductor layer mainly containing silicon, the semiconductor layer has a channel formation region and an impurity region doped with an impurity of one type of conductivity.

Abstract: A method of performing irradiation of laser light is given as a method of crystallizing a semiconductor film. However, if laser light is irradiated to a semiconductor film, the semiconductor film is instantaneously melted and expands locally. The temperature gradient between a substrate and the semiconductor film is precipitous, distortions may develop in the semiconductor film. Thus, the film quality of the crystalline semiconductor film obtained will drop in some cases. With the present invention, distortions of the semiconductor film are reduced by heating the semiconductor film using a heat treatment process after performing crystallization of the semiconductor film using laser light. Compared to the localized heating due to the irradiation of laser light, the heat treatment process is performed over the entire substrate and semiconductor film. Therefore, it is possible to reduce distortions formed in the semiconductor film and to increase the physical properties of the semiconductor film.

Abstract: Contamination of an interface of respective films constituting a TFT due to an contaminant impurity in a clean room atmosphere becomes a great factor to lower the reliability of the TFT. Besides, when an impurity is added to a crystalline semiconductor film, its crystal structure is broken. By using an apparatus for manufacturing a semiconductor device including a plurality of treatment chambers, a treatment can be made without being exposed to a clean room atmosphere in an interval between respective treatment steps, and it becomes possible to keep the interface of the respective films constituting the TFT clean. Besides, by carrying out crystallization after an impurity is added to an amorphous semiconductor film, the breakdown of the crystal structure of the crystalline semiconductor film is prevented.

Abstract: After an amorphous semiconductor thin film is crystallized by utilizing a catalyst element, the catalyst element is removed by performing a heat treatment in an atmosphere containing a halogen element. A resulting crystalline semiconductor thin film exhibits {110} orientation. Since individual crystal grains have approximately equal orientation, the crystalline semiconductor thin film has substantially no grain boundaries and has such crystallinity as to be considered a single crystal or considered so substantially.

Abstract: A method of performing irradiation of laser light is given as a method of crystallizing a semiconductor film. However, if laser light is irradiated to a semiconductor film, the semiconductor film is instantaneously melted and expands locally. The temperature gradient between a substrate and the semiconductor film is precipitous, distortions may develop in the semiconductor film. Thus, the film quality of the crystalline semiconductor film obtained will drop in some cases. With the present invention, distortions of the semiconductor film are reduced by heating the semiconductor film using a heat treatment process after performing crystallization of the semiconductor film using laser light. Compared to the localized heating due to the irradiation of laser light, the heat treatment process is performed over the entire substrate and semiconductor film. Therefore, it is possible to reduce distortions formed in the semiconductor film and to increase the physical properties of the semiconductor film.

Abstract: It is intended to achieve the reduction in number of heat treatments carried out at high temperature (at least 600° C.) and the employment of lower temperature processes (600° C. or lower), and to achieve step simplification and throughput improvement. In the present invention, a barrier layer (105), a second semiconductor film (106), and a third semiconductor layer (108) containing an impurity element (phosphorus) that imparts one conductive type are formed on a first semiconductor film (104) having a crystalline structure. Gettering is carried out in which the metal element contained in the first semiconductor film (104) is allowed to pass through the barrier layer (105) and the second semiconductor film (106) by a heat treatment to move into the third semiconductor film (107). Afterward, the second and third semiconductor films (106) and (107) are removed with the barrier layer (105) used as an etching stopper.

Abstract: An orientation ratio of a crystalline semiconductor film obtained by crystallizing an amorphous semiconductor film is increased, a distortion thereof is suppressed, and a TFT using such a crystalline semiconductor film is provided. At the time of formation of the amorphous semiconductor film (102) or after the formation thereof, a noble gas element, typically, argon is included in the film and crystallization is performed therefor. Thus, an orientation ratio of the semiconductor film (104) can be increased and a distortion present in the semiconductor film (104) after the crystallization is suppressed as compared with that present in the semiconductor film before the crystallization. Then, the noble gas element in the film is removed or reduced by laser light irradiation performed later.