Method and apparatus for forming contact hole

Abstract

A method of forming a contact hole in an insulating film coating amorphous Si having an irregular surface formed on an insulating substrate, for connecting the amorphous Si to a conductor film formed on the insulating film includes etching the insulating film using reactive ion etching to a depth whereat the irregularity does not disappear, and sputter-etching by physically colliding Ar radicals produced by Ar gas plasma discharge onto the surface of the amorphous Si.

1 . A method of forming a contact hole in an insulating film coating amorphous Si having an irregular surface formed on an insulating substrate, for connecting said amorphous Si to a conductor film formed on said insulating film, said method comprising:
 etching said insulating film using reactive ion etching to a depth whereat said irregularity does not disappear; and   sputter-etching by physically colliding Ar radicals produced by Ar gas plasma discharge onto the surface of said amorphous Si.   
     
     
         2 . The method of forming a contact hole according to  claim 1 , wherein a fluorine-based gas is used in said reactive ion etching. 
     
     
         3 . The method of forming a contact hole according to  claim 1 , wherein said insulating substrate comprises glass. 
     
     
         4 . The method of forming a contact hole according to  claim 1 , wherein said insulating substrate comprises a plastic. 
     
     
         5 . A method of forming a contact hole in an insulating film coating amorphous Si having an irregular surface formed on an insulating substrate, for connecting said amorphous Si to a conductor film formed on said insulating film, said method comprising, in a following order:
 etching said insulating film using reactive ion etching to a depth whereat said irregularity does not disappear;   removing a byproduct of said reactive ion etching using wet etching;   sputter-etching the surface of said amorphous Si; and   forming a metallic film in said surface of said amorphous Si using sputtering.   
     
     
         6 . The method of forming a contact hole according to  claim 5 , wherein buffered hydrofluoric acid is used as an etchant for said wet etching. 
     
     
         7 . The method of forming a contact hole according to  claim 5 , wherein a fluorine-based gas is used in said reactive ion etching. 
     
     
         8 . The method of forming a contact hole according to  claim 5 , wherein after completion of said sputter etching, said substrate is transferred into an AlSi film-forming sputtering chamber through a transfer path maintained in one of a vacuum state, and a state filled with an inert gas, and said metallic film is formed. 
     
     
         9 . A contact hole forming apparatus for forming a contact hole in an insulating film coating amorphous Si having an irregular surface formed on an insulating substrate, for connecting said amorphous Si to a conductor film formed on said insulating film, said apparatus comprising:
 an etching chamber that performs sputter etching;   an AlSi film-forming sputtering chamber that forms an AlSi film; and   a transfer mechanism that transfers said substrate from said etching chamber to said AlSi film-forming sputtering chamber in one of a vacuum state, and a state filled with an inert gas.   
     
     
         10 . The method of forming a contact hole according to  claim 9 , wherein said insulating substrate comprises glass. 
     
     
         11 . The method of forming a contact hole according to  claim 9 , wherein said insulating substrate comprises a plastic. 
     
     
         12 . An amorphous Si device, wherein an amorphous Si contacts a metallic wiring in a contacting area, said contacting area has a surface roughness of 10 nm or less. 
     
     
         13 . A liquid crystal display including the amorphous Si device according to  claim 12  in a liquid crystal drive circuit. 
     
     
         14 . A method of forming a contact hole in an insulating film coating amorphous Si having an irregular surface formed on an insulating substrate, for connecting said amorphous Si to a conductor film formed on said insulating film, said method comprising:
 etching said insulating film using reactive ion etching to a depth whereat said irregularity does not disappear;   removing a byproduct of said reactive ion etching using wet etching; and   sputter-etching the surface of said amorphous Si,   wherein said etching, said removing, and said sputter-etching are conducted in sequence.   
     
     
         15 . A method of forming a contact hole in an insulating film coating amorphous Si having an irregular surface formed on an insulating substrate, for connecting said amorphous Si to a conductor film formed on said insulating film, said method comprising:
 etching said insulating film using reactive ion etching to a depth whereat said irregularity does not disappear; and   sputter-etching by physically colliding Ar radicals produced by Ar gas plasma discharge onto the surface of said amorphous Si,   wherein said etching and said sputter-etching are conducted in sequence.   
     
     
         16 . A contact hole forming apparatus for forming a contact hole in an insulating film coating amorphous Si having an irregular surface formed on a glass substrate, for connecting said amorphous Si to a conductor film formed on said insulating film, said apparatus comprising:
 an etching chamber for performing sputter etching;   an AlSi film-forming sputtering chamber for forming an AlSi film; and   a transfer mechanism for transferring said glass substrate from said etching chamber to said film-forming chamber in a vacuum state, or a state filled with an inert gas.