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: 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 &mgr;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: 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 &mgr;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: 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: 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: 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: 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 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: 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: The number of grains in active regions of devices can be made uniform by making the grains of crystalline semiconductor films, obtained by thermal crystallization using a metal element, smaller. The present invention is characterized in that a semiconductor film is exposed within an atmosphere in which a gas, having as its main constituent one or a plurality of members from the group consisting of inert gas elements, nitrogen, and ammonia, is processed into a plasma, and then thermal crystallization using a metal element is performed. The concentration of crystal nuclei1 generated is thus increased, making the grain size smaller, by performing these processes. Heat treatment may also be performed, of course, after exposing the semiconductor film, to which the metal element is added, to an atmosphere in which a gas, having as its main constituent one or a plurality of members from the group consisting of inert gas elements, nitrogen, and ammonia, is processed into a plasma.

Abstract: An object is to reduce the number of high temperature (equal to or greater than 600° C.) heat treatment process steps and achieve lower temperature (equal to or less than 600° C.) processes, and to simplify the process steps and increase throughput in a method of manufacturing a semiconductor device. With the present invention, a barrier layer, a second semiconductor film, and a third semiconductor film containing an inert gas element are formed on a first semiconductor film having a crystalline structure. Gettering is performed and a metallic element contained in the first semiconductor film passes through the barrier layer and the second semiconductor film by a heat treatment process, and moves to the third semiconductor film. The second semiconductor film and the third semiconductor film are then removed, with the barrier layer used as an etching stopper.

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: 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 crystallization method by laser light irradiation forms a multiplicity of convexes (ridges) in the surface of an obtained crystalline semiconductor film, deteriorating film quality. Therefore, it is a problem to provide a method for forming a ridge-reduced semiconductor film and a semiconductor device using such a semiconductor film. The present invention is characterized by heating a semiconductor film due to a heat processing method (RTA method: Rapid Thermal Anneal method) to irradiate light emitted from a lamp light source after crystallizing the semiconductor film by laser light, thereby reducing the ridge.

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: To provide a semiconductor device utilizing a semiconductor film having a high crystallinity by a production process having a high mass productivity. Upon crystallizing an amorphous silicon film 106, germanium is used as a catalyst element for accelerating the crystallization. A heat treatment is conducted in a condition in that a germanium film 107 is formed on the amorphous silicon film 106, and thus a polysilicon film 108 is obtained by the catalytic function of germanium. The polysilicon film 108 thus obtained has crystallinity that can be substantially regarded as a single crystal.

Abstract: In a crystalline silicon film fabricated by a related art method, the orientation planes of its crystal randomly exist and the orientation rate relative to a particular crystal orientation is low. A semiconductor material which contains silicon as its main component and 0.1-10 atomic % of germanium is used as a first layer, and an amorphous silicon film is used as a second layer. Laser light is irradiated to crystallize the amorphous semiconductor films, whereby a good semiconductor film is obtained. In addition, TFTs are fabricated by using such a semiconductor film.

Abstract: Crystal orientation planes exist randomly in a crystalline silicon film manufactured by a conventional method, and the orientation ratio is low with respect to a specific crystal orientation. A semiconductor film having a high orientation ratio for the {101} lattice plane is obtained if crystallization of an amorphous semiconductor film, which has silicon as its main constituent and contains from 0.1 to 10 atom % germanium, is performed after introduction of a metal element. A TFT is manufactured utilizing the semiconductor film.

Abstract: A semiconductor device comprising a substrate having an insulating surface layer and an active layer comprising a semiconductor thin film formed thereon, wherein the substrate and the insulating surface layer in contact with the substrate each has at least one concave part, and the influence of the concave part is removed by conducting a flattening treatment and heat treatment of the undercoat film of the semiconductor thin film.