Manufacturing method of semiconductor devices by using dry etching technology

Abstract

There is provided a method of forming an interlayer insulating film having a dual-damascene structure, a contact hole and a deep trench mask using an organic silicon film. The shape of polysilane or the like is processed so that polysilane is used as an interlayer insulating film having a dual-damascene structure to control the shape and depth and prevent borderless etching which must be solved when a trench is formed. Polysilane and an insulating film are formed into a laminated structure so as to be integrated with each other after a dry etching step has been completed to easily form a contact hole having a high aspect ratio. The surface of polysilane is selectively formed into an insulating film so as to be used as a mask for use in a dry etching step. Polysilane for use as an anti-reflective film or an etching mask is changed to an oxide film or a nitride film so that films are easily removed. Hence it follows that a device region and a device isolation region of a densely integrated circuit can be smoothed, a self-aligned contact hole and metallization trench can be formed with a satisfactory manufacturing yield and the pattern of a gate electrode can be formed.

What is claimed is:  
     
         1 . A manufacturing method of semiconductor devices by using dry etching technology comprising the steps of: 
 forming an organic silicon film on a semiconductor substrate;    dry-etching the organic silicon film to form a portion which is predetermined to be constituted by the insulating film of the semiconductor device by using the organic silicon film; and changing the organic silicon film into an insulating film so that the portion of the semiconductor device constituted by the insulating film is formed.    
     
     
         2 . A manufacturing method of semiconductor devices according to  claim 1 , wherein the organic silicon film has bondings of silicon and silicon as main chains thereof.  
     
     
         3 . A manufacturing method of semiconductor devices according to  claim 1 , wherein at least any one of oxygen, nitrogen, hydrogen and carbon elements is introduced into the organic silicon film following dry etching of the organic silicon film so that the organic silicon film is changed to any one of organic silicon oxide film, an inorganic silicon oxide film, a silicon oxide film, a silicon nitride film and a silicon oxynitride film.  
     
     
         4 . A manufacturing method of semiconductor devices according to  claim 3 , wherein the step of introducing at least any one of oxygen, nitrogen, hydrogen and carbon elements into the organic silicon film is performed by using any one of a reactive ion etching method, an ashing method and an ion implanting method using ions of the elements or a mixture of the elements.  
     
     
         5 . A manufacturing method of semiconductor devices according to  claim 3 , wherein the step of introducing at least any one of oxygen, nitrogen, hydrogen and carbon elements into the organic silicon film is performed by performing heat treatment in a gas atmosphere composed of the element or a mixture of the elements.  
     
     
         6 . A manufacturing method of semiconductor devices according to  claim 1 , wherein the portion constituted by the insulating film of the semiconductor device is formed by at least any one of an interlayer insulating film between the surface of the semiconductor substrate and a lower metallization layer of a dual-damascene structure, an insulating film for burying the space between wiring metals formed in each metallization layer of the dual-damascene structure and an interlayer insulating film between upper and lower metallization layers of the dual-damascene structure.  
     
     
         7 . A manufacturing method of semiconductor devices according to  claim 6 , wherein the organic silicon film is laminated on the insulating film and the insulating film is employed as a suppression layer of the dry etching.  
     
     
         8 . A manufacturing method of semiconductor devices according to  claim 1 , wherein the portion constituted by the insulating film of the semiconductor device is formed by an interlayer insulating film including a contact hole of the dual-damascene structure formed on the semiconductor substrate and a trench in each of the upper and lower metallization layers of the dual-damascene structure.  
     
     
         9 . A manufacturing method of semiconductor devices according to  claim 8 , wherein 
 the step of forming the contact hole incorporates the steps of: 
 coating the overall upper surface of the lower metallization layer with the organic silicon film,  
 providing the contact hole which reaches the upper surface of the wiring metal in the lower metallization layer for the organic silicon film by selectively dry-etching the organic silicon film and  
 changing the organic silicon film in which the contact hole has been formed into any one of an organic silicon oxide film, an inorganic silicon oxide film, a silicon oxide film, a silicon nitride film and a silicon oxynitride film.  
   
     
     
         10 . A manufacturing method of semiconductor devices according to  claim 9 , wherein the lower metallization layer is constituted by a trench metallization buried in the insulating film of the semiconductor substrate, and the upper surface of the insulating film suppresses borderless etching when the contact hole is formed.  
     
     
         11 . A manufacturing method of semiconductor devices according to  claim 8 , wherein 
 the step of forming the trench includes the steps of: 
 coating the overall upper surface of the insulating film on the semiconductor substrate with the organic silicon film,  
 removing the portion of the organic silicon film in which the trench has been formed by selectively dry-etching the organic silicon film and  
 changing the organic silicon film subjected to the removal step into an insulating film constituted by any one of an organic silicon oxide film, an inorganic silicon oxide film, a silicon oxide film, a silicon nitride film and a silicon oxynitride film.  
   
     
     
         12 . A manufacturing method of semiconductor devices according to  claim 8 , wherein the step of forming the interlayer insulating film includes the steps of: 
 forming the contact hole in the insulating film on the semiconductor substrate,    coating the overall upper surface of the insulating film with the organic silicon film such that the contact hole is buried,    removing a portion of the upper metallization layer including an opening portion of the contact hole in which the trench has been formed and the organic silicon film in the contact hole by selectively dry-etching the organic silicon film and    changing the organic silicon film subjected to the removal step into an insulating film constituted by any one of an organic silicon oxide film, an inorganic silicon oxide film, a silicon oxide film, a silicon nitride film and a silicon oxynitride film.    
     
     
         13 . A manufacturing method of semiconductor devices according to  claim 12 , wherein the step of removing the organic silicon film is performed such that the upper surface of the insulating film on the semiconductor substrate controls the dry etching so that the organic silicon film is selectively etched.  
     
     
         14 . A manufacturing method of semiconductor devices according to  claim 8 , wherein the step of forming the interlayer insulating film includes: 
 a step of coating the overall upper surface of a first insulating film on the semiconductor substrate on which the lower metallization layer has been formed with the organic silicon film,    a first selective dry etching step of forming a contact hole which reaches the upper surface of the metallization of the lower metallization layer,    a step of changing the organic silicon film having the contact hole into a second insulating film constituted by any one of an organic silicon oxide film, an inorganic silicon oxide film, a silicon oxide film, a silicon nitride film and a silicon oxynitride film,    a step of coating the overall upper surface of the second insulating film with the organic silicon film,    a second selective dry etching step of forming a trench in the upper metallization layer connected to the contact hole formed on the second insulating film by removing the organic silicon film in the portion of the upper metallization layer including the opening portion of the contact hole on which the trench has been formed and the inside portion of the contact hole and    a step of changing the organic silicon film having the trench in the upper metallization layer into a third insulating film constituted by any one of an organic silicon oxide film, an inorganic silicon oxide film, a silicon oxide film, a silicon nitride film and a silicon oxynitride film.    
     
     
         15 . A manufacturing method of semiconductor devices according to  claim 14 , wherein the first insulating film suppresses borderless etching occurring in the periphery of the lower metallization layer in the first dry etching step, and the second insulating film controls the second selective dry etching step of forming the trench in the upper metallization layer.  
     
     
         16 . A manufacturing method of semiconductor devices according to  claim 8 , wherein the step of forming the interlayer insulating film includes the steps of: 
 forming any one of a first organic silicon oxide film, an inorganic silicon oxide film and a silicon oxide film on the insulating film on the semiconductor substrate on which the lower metallization layer has been formed,    forming a stopper for dry etching constituted by an organic silicon film on any one of the first organic silicon oxide film, the inorganic silicon oxide film and the silicon oxide film,    providing an opening portion for forming the contact hole which reaches the lower metallization layer for the stopper,    forming any one of a second organic silicon oxide film, an inorganic silicon oxide film and a silicon oxide film such that the stopper having the opening portion is buried,    forming an etching mask for forming a trench of the metallization layer to correspond to the opening portion, and    continuously and selectively dry-etching any one of the first and second organic silicon oxide film, the incorporate silicon oxide film and the silicon oxide film by using the etching mask and the stopper having the opening portion.    
     
     
         17 . A manufacturing method of semiconductor devices according to  claim 16 , wherein a step is included in which the stopper for dry etching constituted by the organic silicon film is subjected to the step of continuously and selectively dry-etching any one of the first and second organic silicon oxide film, the inorganic silicon oxide film and the silicon oxide film and changed into an organic silicon oxide film so as to be integrated as a portion of the interlayer insulating film.  
     
     
         18 . A manufacturing method of semiconductor devices by using dry etching technology, comprising the steps of: 
 forming an organic silicon film having bondings of silicon and silicon as the main chains thereof on a semiconductor substrate and selectively introducing any one of oxygen, nitrogen, hydrogen and carbon elements into at least the surface of the organic silicon film,    forming a portion of the semiconductor device constituted by insulating material by performing selective dry etching such that the surface of the organic silicon film is used as a mask; and    introducing at least any one of oxygen, nitrogen, hydrogen and carbon elements into the organic silicon film after the organic silicon film has been dry-etched to integrate both of the surface of the organic silicon film and the inside portion of the organic silicon film as any one of an organic silicon oxide film, an inorganic silicon oxide film, a silicon oxide film, a silicon nitride film and a silicon oxynitride film.    
     
     
         19 . A manufacturing method of semiconductor devices according to  claim 18 , wherein selective dry etching is performed such that the surface of the organic silicon film is used as a mask to process the edge in the periphery of the opening portion of the mask to be rounded.  
     
     
         20 . A manufacturing method of semiconductor devices by using dry etching technology comprising the steps of: 
 forming an organic silicon film having bondings of silicon and silicon as the main chains thereof on a semiconductor substrate and selectively introducing any one of oxygen, nitrogen, hydrogen and carbon elements into at least the surface of the organic silicon film;    forming a portion of the semiconductor device constituted by insulating material by performing selective dry etching such that the surface of the organic silicon film is used as a mask;    introducing at least any one of oxygen, nitrogen, hydrogen and carbon elements into the organic silicon film after the organic silicon film has been dry-etched to make the surface of the organic silicon film and the inside portion of the organic silicon film to be constituted by different type films which are an organic silicon oxide film, an inorganic silicon oxide film, a silicon oxide film, a silicon nitride film and a silicon oxynitride film; and    removing the mask by performing selective etching of the surface of the organic silicon film and the inside portion of the organic silicon film.    
     
     
         21 . A manufacturing method of semiconductor devices by using dry etching technology, comprising the steps of: 
 using an organic silicon film to form an anti-reflective film for use in a photolithography step on the upper surface of the insulating film on a semiconductor substrate;    introducing any one of oxygen, nitrogen, hydrogen and carbon elements into the organic silicon film after the photolithography step has been completed to constitute the anti-reflective film by any one of an organic silicon oxide film, an inorganic silicon oxide film, a silicon oxide film, a silicon nitride film and a silicon oxynitride film; and    integrating the anti-reflective film and the insulating film with each other.    
     
     
         22 . A manufacturing method of semiconductor devices by using dry etching technology, comprising the steps of: 
 using an organic silicon film to form an anti-reflective film for use in a photolithography step on the upper surface of the insulating film on a semiconductor substrate;    introducing any one of oxygen, nitrogen, hydrogen and carbon elements into the organic silicon film after the photolithography step has been completed to constitute the anti-reflective film by any one of an organic silicon oxide film, an inorganic silicon oxide film, a silicon oxide film, a silicon nitride film and a silicon oxynitride film; and    removing the anti-reflective film by etching by using selective etching of the anti-reflective film and the insulating film subjected to the process.    
     
     
         23 . A manufacturing method of semiconductor devices by using dry etching technology comprising the steps of: 
 forming a thermal oxide film on a semiconductor substrate;    forming a silicon oxide film on the organic silicon film by coating the thermal oxide film with an organic silicon film;    forming an opening portion which reaches the surface of the semiconductor substrate on a multilayered film constituted by the silicon oxide film and the organic silicon film;    changing the organic silicon film to a silicon nitride film by introducing nitrogen into the organic silicon film subjected to the step; and    forming a trench on the semiconductor substrate by using a multilayered film constituted by the silicon oxide film and the silicon nitride film, as a mask.    
     
     
         24 . A manufacturing method of semiconductor devices by using dry etching technology comprising the steps of: 
 coating a semiconductor substrate with an organic silicon film and forming the pattern of the organic silicon film by using a resist as a mask such that a device region on the semiconductor substrate is covered; and    forming an isolation trench in the semiconductor substrate by using the organic silicon film, the pattern of which has been formed, and the resist as masks and changing the organic silicon film to a silicon nitride film by introducing nitrogen into the organic silicon film.    
     
     
         25 . A manufacturing method of semiconductor devices according to  claim 24 , further comprises the steps of: 
 furthermore coating the overall upper surface of the semiconductor substrate, on which the isolation trench has been formed, with the organic silicon film such that the isolation trench is buried;    smoothing the surface of the organic silicon film by using the semiconductor as a suppression layer; and    changing the organic silicon film into any one of a silicon oxide film, an organic silicon oxide film and an inorganic silicon oxide film by introducing oxygen into the organic silicon film with which the isolation trench is buried.    
     
     
         26 . A manufacturing method of semiconductor devices by using dry etching technology comprising the steps of: 
 forming a gate insulating film on a semiconductor substrate and forming at least one metallic film on the gate insulating film;    forming the pattern of the organic silicon film in a region of the semiconductor substrate which has been covered with the mask and in which the gate electrode has been formed such that a resist is used as a mask;    forming the pattern of a gate electrode constituted by the metallic film in the region in which the gate electrode has been formed such that the organic silicon film, the pattern of which has been formed, and the resist are used as masks; and    changing the organic silicon film, the pattern of which has been formed, into a nitride film by introducing nitrogen into the organic silicon film.    
     
     
         27 . A manufacturing method of semiconductor devices by using dry etching technology comprising the steps of: 
 forming a gate insulating film on a semiconductor substrate, forming at least one metallic film on the gate electrode insulating film and forming the pattern of a gate electrode constituted by the metallic film on a region of the semiconductor substrate which is covered with the metallic film and in which a gate electrode will be formed;    covering the gate electrode with a silicon nitride film and depositing a first insulating film on the overall upper surface of the semiconductor substrate such that the gate electrode is buried;    smoothing the surface of the first insulating film and coating the surface of the smoothed first insulating film with an organic silicon film;    forming a contact hole which reaches the first insulating film in the organic silicon film by selectively removing the organic silicon film which covers a region adjacent to the gate electrode in which either of a source or a drain will be formed and a portion of the gate electrode adjacent to the source or the drain by performing dry etching using a resist as a mask;    exposing the silicon nitride film to the bottom portion of the contact hole by dry-etching the first insulating film by using the resist and the organic silicon film as masks;    in a self-aligning manner, exposing the surface of either of region on the surface of the semiconductor substrate in which the source will be formed or a region in which the drain will be formed by removing the silicon nitride film and the gate insulation film by further etching; and    integrating the organic silicon film with the first insulating film and using the contact hole to connect metallizations by changing the organic silicon film into a second insulating film constituted by any one of an organic silicon oxide film, an inorganic silicon oxide film, a silicon oxide film, a silicon nitride film and a silicon oxynitride film.    
     
     
         28 . A manufacturing method of semiconductor devices by using dry etching technology comprising the steps of: 
 forming a gate insulating film on a semiconductor substrate, forming at least one metallic film on the gate insulating film and forming the pattern of a gate electrode constituted by the metallic film in a region of the semiconductor substrate which is covered with the metallic film and in which the gate electrode will be formed;    furthermore covering the first silicon oxide film by covering the gate electrode with a silicon nitride film and depositing the gate electrode on the silicon nitride film;    forming a contact hole which reaches the first silicon oxide film in the organic silicon film by coating the overall upper surface of the semiconductor substrate with the organic silicon film and by selectively removing the organic silicon film which covers a region adjacent to the gate electrode in which a source or a drain will be formed and a portion of the gate electrode adjacent to the portion in which the source or the drain will be formed by performing dry etching which uses a resist as a mask;    removing the first silicon oxide film exposed to the bottom surface of the contact hole by introducing oxygen into the organic silicon film to change the organic silicon film into a second silicon oxide film and by performing dry etching such that the second silicon oxide film is used as a mask; and    in a self-alignment manner, exposing the surface of the region which has been formed on the semiconductor substrate and in which the source or the drain will be formed and using the contact hole for connecting metallizations by further removing the silicon nitride film and gate insulating film exposed owing to removal of the first silicon oxide film.    
     
     
         29 . A dry etching method comprising the steps of: 
 forming an organic silicon film having main chains thereof constituted by bondings of silicon and silicon on a semiconductor substrate and forming a portion of the semiconductor device constituted by insulating material by dry-etching at least the organic silicon film; and    changing a portion of the organic silicon film into an insulating film constituted by any one of an organic silicon oxide film, an inorganic silicon oxide film, a silicon oxide film, a silicon nitride film and a silicon oxynitride film by processing the processed organic silicon film by executing at least heat treatment which is performed in O 2 , N 2  or H 2  gas, heat treatment which is performed in O 2 , N 2  or H 2  plasma or implantation of O 2 , N 2  or H 2  ions and heat treatment.