Method of manufacturing a semiconductor device

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.

What is claimed is:  
     
         1 . A method of manufacturing a semiconductor device comprising: 
 a first step of forming an amorphous semiconductor film over a substrate;    a second step of crystallizing the amorphous semiconductor film by a heat treatment;    a third step of removing a contaminant impurity on a surface of the crystallized semiconductor film; and    a fourth step of irradiating the crystallized semiconductor film with a laser light after the third step,    wherein the third step and the fourth step are continuously conducted.    
     
     
         2 . A method according to  claim 1 , wherein the step of removing the contaminant impurity is conducted in an acid solution containing fluorine.  
     
     
         3 . A method according to  claim 1 , wherein the step of removing the contaminant impurity is conducted in an acid solution containing fluorine, after washing by pure water in which ozone is dissolved.  
     
     
         4 . A method according to  claim 1 , wherein the contaminant impurity is one element or a plurality of elements existing in an air.  
     
     
         5 . A method according to  claim 1 , wherein the laser comprises an excimer laser or a YAG laser.  
     
     
         6 . A method according to  claim 1 , wherein the semiconductor device is an electro-luminescence display device.  
     
     
         7 . A method according to  claim 1 , wherein the semiconductor device is at least one selected from the group consisting of a video camera, a digital camera, a projector, a head-mount display, a car navigation system, a personal computer, a player using a recording medium, a portable electronic book, and a mobile telephone.  
     
     
         8 . A method of manufacturing a semiconductor device comprising: 
 a first step of forming a base film on a substrate;    a second step of forming an amorphous semiconductor film on the base film;    a third step of forming an insulating film on the amorphous semiconductor film;    a fourth step of adding an impurity element to the amorphous semiconductor film;    a fifth step of crystallizing the amorphous semiconductor film by a heat treatment after the fourth step;    a sixth step of removing a contaminant impurity on a surface of the crystallized semiconductor film; and    a seventh step of irradiating the crystallized semiconductor film with a laser light after the sixth step,    wherein the first through the third steps are conducted without being exposed to an air, and    wherein the sixth step and the seventh step are continuously conducted.    
     
     
         9 . A method according to  claim 8 , wherein the step of removing the contaminant impurity is conducted in an acid solution containing fluorine.  
     
     
         10 . A method according to  claim 8 , wherein the step of removing the contaminant impurity is conducted in an acid solution containing fluorine, after washing by pure water in which ozone is dissolved.  
     
     
         11 . A method according to  claim 8 , wherein the contaminant impurity is one element or a plurality of elements existing in an air.  
     
     
         12 . A method according to  claim 8 , wherein the laser comprises an excimer laser or a YAG laser.  
     
     
         13 . A method according to  claim 8 , wherein the semiconductor device is an electro-luminescence display device.  
     
     
         14 . A method according to  claim 8 , wherein the semiconductor device is at least one selected from the group consisting of a video camera, a digital camera, a projector, a head-mount display, a car navigation system, a personal computer, a player using a recording medium, a portable electronic book, and a mobile telephone.  
     
     
         15 . A method of manufacturing a semiconductor device comprising: 
 a first step of forming a base film on a substrate;    a second step of forming an amorphous semiconductor film on the base film;    a third step of crystallizing the amorphous semiconductor film by irradiating a laser light;    a fourth step of forming an insulating film on the crystallized semiconductor film; and    a fifth step of adding an impurity element to the crystallized semiconductor film,    wherein the first through the fifth steps are continuously conducted.    
     
     
         16 . A method according to  claim 15 , wherein the laser comprises an excimer laser or a YAG laser.  
     
     
         17 . A method according to  claim 15 , wherein the semiconductor device is an electro-luminescence display device.  
     
     
         18 . A method according to  claim 15 , wherein the semiconductor device is at least one selected from the group consisting of a video camera, a digital camera, a projector, a head-mount display, a car navigation system, a personal computer, a player using a recording medium, a portable electronic book, and a mobile telephone.  
     
     
         19 . A method of manufacturing a semiconductor device comprising: 
 a first step of forming a base film on a substrate;    a second step of forming an amorphous semiconductor film on the base film;    a third step of crystallizing the amorphous semiconductor film by irradiating a first laser light;    a fourth step of forming an insulating film on the crystallized semiconductor film;    a fifth step of adding an impurity element to the crystallized semiconductor film; and    a sixth step of irradiating the crystallized semiconductor film with a second laser light,    wherein the first through the sixth steps are continuously conducted.    
     
     
         20 . A method according to  claim 19 , wherein the laser comprises an excimer laser or a YAG laser.  
     
     
         21 . A method according to  claim 19 , wherein the semiconductor device is an electro-luminescence display device.  
     
     
         22 . A method according to  claim 19 , wherein the semiconductor device is at least one selected from the group consisting of a video camera, a digital camera, a projector, a head-mount display, a car navigation system, a personal computer, a player using a recording medium, a portable electronic book, and a mobile telephone.  
     
     
         23 . A method of manufacturing a semiconductor device comprising: 
 a first step of forming an amorphous semiconductor film over a substrate;    a second step of crystallizing the amorphous semiconductor film by a heat treatment;    a third step of removing a contaminant impurity on a surface of the crystallized semiconductor film; and    a fourth step of irradiating the crystallized semiconductor film with a continuous-wave laser light after the third step,    wherein the third step and the fourth step are continuously conducted.    
     
     
         24 . A method according to  claim 23 , wherein the step of removing the contaminant impurity is conducted in an acid solution containing fluorine.  
     
     
         25 . A method according to  claim 23 , wherein the step of removing the contaminant impurity is conducted in an acid solution containing fluorine, after washing by pure water in which ozone is dissolved.  
     
     
         26 . A method according to  claim 23 , wherein the contaminant impurity is one element or a plurality of elements existing in an air.  
     
     
         27 . A method according to  claim 23 , wherein the laser comprises an excimer laser or a YAG laser.  
     
     
         28 . A method according to  claim 23 , wherein the semiconductor device is an electro-luminescence display device.  
     
     
         29 . A method according to  claim 23 , wherein the semiconductor device is at least one selected from the group consisting of a video camera, a digital camera, a projector, a head-mount display, a car navigation system, a personal computer, a player using a recording medium, a portable electronic book, and a mobile telephone.  
     
     
         30 . A method of manufacturing a semiconductor device comprising: 
 a first step of forming a base film on a substrate;    a second step of forming an amorphous semiconductor film on the base film;    a third step of forming an insulating film on the amorphous semiconductor film;    a fourth step of adding an impurity element to the amorphous semiconductor film;    a fifth step of crystallizing the amorphous semiconductor film by a heat treatment after the fourth step;    a sixth step of removing a contaminant impurity on a surface of the crystallized semiconductor film; and    a seventh step of irradiating the crystallized semiconductor film with a continuous-wave laser light after the sixth step,    wherein the first through the third steps are conducted without being exposed to an air, and    wherein the sixth step and the seventh step are continuously conducted.    
     
     
         31 . A method according to  claim 30 , wherein the step of removing the contaminant impurity is conducted in an acid solution containing fluorine.  
     
     
         32 . A method according to  claim 30 , wherein the step of removing the contaminant impurity is conducted in an acid solution containing fluorine, after washing by pure water in which ozone is dissolved.  
     
     
         33 . A method according to  claim 30 , wherein the contaminant impurity is one element or a plurality of elements existing in an air.  
     
     
         34 . A method according to  claim 30 , wherein the laser comprises an excimer laser or a YAG laser.  
     
     
         35 . A method according to  claim 30 , wherein the semiconductor device is an electro-luminescence display device.  
     
     
         36 . A method according to  claim 30 , wherein the semiconductor device is at least one selected from the group consisting of a video camera, a digital camera, a projector, a head-mount display, a car navigation system, a personal computer, a player using a recording medium, a portable electronic book, and a mobile telephone.  
     
     
         37 . A method of manufacturing a semiconductor device comprising: 
 a first step of forming a base film on a substrate;    a second step of forming an amorphous semiconductor film on the base film;    a third step of crystallizing the amorphous semiconductor film by irradiating a first continuous-wave laser light;    a fourth step of forming an insulating film on the crystallized semiconductor film; and    a fifth step of adding an impurity element to the crystallized semiconductor film,    wherein the first through the fifth steps are continuously conducted.    
     
     
         38 . A method according to  claim 37 , wherein the laser comprises an excimer laser or a YAG laser.  
     
     
         39 . A method according to  claim 37 , wherein the semiconductor device is an electro-luminescence display device.  
     
     
         40 . A method according to  claim 37 , wherein the semiconductor device is at least one selected from the group consisting of a video camera, a digital camera, a projector, a head-mount display, a car navigation system, a personal computer, a player using a recording medium, a portable electronic book, and a mobile telephone.  
     
     
         41 . A method of manufacturing a semiconductor device comprising: 
 a first step of forming a base film on a substrate;    a second step of forming an amorphous semiconductor film on the base film;    a third step of crystallizing the amorphous semiconductor film by irradiating a first continuous-wave laser light;    a fourth step of forming an insulating film on the crystallized semiconductor film;    a fifth step of adding an impurity element to the crystallized semiconductor film; and    a sixth step of irradiating the crystallized semiconductor film with a second continuous-wave laser light,    wherein the first through the sixth steps are continuously conducted.    
     
     
         42 . A method according to  claim 41 , wherein the laser comprises an excimer laser or a YAG laser.  
     
     
         43 . A method according to  claim 41 , wherein the semiconductor device is an electro-luminescence display device.  
     
     
         44 . A method according to  claim 41 , wherein the semiconductor device is at least one selected from the group consisting of a video camera, a digital camera, a projector, a head-mount display, a car navigation system, a personal computer, a player using a recording medium, a portable electronic book, and a mobile telephone.