Ultraviolet-light radiating apparatus, wet etching apparatus and wet etching method using ultravioletlight, and method of manufacturing semiconductor device

Abstract

A substrate supporting film to be etched is held on a rotating stage. Ultraviolet light having a wavelength of 200 nm or shorter radiated from first lamps irradiates the film in air, thereby removing organic coatings from the film and making the surface of the film hydrophilic. A chemical solution applied to the hydrophilic film while rotating the substrate. Ultraviolet light having a wavelength longer than 200 nm is radiated from second lamps and onto the film through the chemical solution.

1 . An ultraviolet-light radiating apparatus for irradiating with ultraviolet light a film that is to be processed and that is supported on a substrate, comprising: 
 first ultraviolet-light radiating units for radiating ultraviolet light having a wavelength not exceeding 200 nm; and    second ultraviolet-light radiating units for radiating ultraviolet light having a wavelength longer than 200 nm.    
     
     
         2 . The ultraviolet-light radiating apparatus according to  claim 1 , further comprising a storage unit for accommodating the first and second ultraviolet-light radiating units and having a light-transmitting window facing the film, wherein the storage unit is filled with an inert gas.  
     
     
         3 . The ultraviolet-light radiating apparatus according to  claim 1 , wherein the second ultraviolet-light radiating units radiate ultraviolet light having energy higher than binding energy of constituent molecules of the film.  
     
     
         4 . A wet etching apparatus comprising: 
 a stage for holding a substrate supporting a film to be etched;    first ultraviolet radiating units for irradiating the film with ultraviolet light having a wavelength not exceeding 200 nm;    a chemical-solution coating unit for applying a coating of chemical solution to the film; and    second ultraviolet radiating units for irradiating the film through the coating of the chemical solution with ultraviolet light having a wavelength longer than 200 nm.    
     
     
         5 . The etching apparatus according to  claim 4 , wherein the stage holds the substrate in an ambient including oxygen.  
     
     
         6 . The etching apparatus according to  claim 4 , wherein the second ultraviolet radiating units radiate ultraviolet light having energy higher than binding energy of constituent molecules of the film.  
     
     
         7 . A wet etching method comprising: 
 irradiating a film to be etched and on a substrate with ultraviolet light having a wavelength not exceeding 200 nm;    applying a coating of a chemical solution to the film after irradiating the film with ultraviolet light having a wavelength not exceeding 200 nm; and    irradiating with the film through the chemical solution with ultraviolet light having a wavelength longer than 200 nm.    
     
     
         8 . The wet etching method according to  claim 7 , including irradiating the film with the ultraviolet light having a wavelength not exceeding 200 nm in an ambient including oxygen to generate oxygen radicals and ozone proximate the film.  
     
     
         9 . The wet etching method according to  claim 8 , wherein an organic coating formed on a surface of the film is removed by the oxygen radicals and ozone.  
     
     
         10 . The wet etching method according to  claim 7 , including irradiating the film with the ultraviolet light having a wavelength longer than 200 nm and having energy higher than binding energy of constituent molecules of the film.  
     
     
         11 . A method of manufacturing a semiconductor device, comprising: 
 forming a high-k dielectric film on a substrate;    forming a gate electrode on the high-k dielectric film;    irradiating the high-k dielectric film with ultraviolet light having a wavelength not exceeding 200 nm;    applying a coating of a chemical solution to the high-k dielectric film after irradiating with the ultraviolet light having a wavelength not exceeding 200 nm;    irradiating the high-k dielectric film, through the chemical solution, with ultraviolet light having a wavelength longer than 200 nm; and    forming diffusion regions in the substrate after irradiating with the ultraviolet light having a wavelength longer than 200 nm.    
     
     
         12 . The method of manufacturing a semiconductor device according to  claim 11 , including irradiating the high-k dielectric film with the ultraviolet light having a wavelength not exceeding 200 nm in an ambient including oxygen to generate oxygen radicals and ozone of proximate the high-k dielectric film.  
     
     
         13 . The method of manufacturing a semiconductor device according to  claim 12 , wherein an organic coating formed on a surface of the high-k dielectric film is removed by the oxygen radicals and ozone.  
     
     
         14 . The method of manufacturing a semiconductor device according to  claim 11 , including the irradiating the high-k dielectric film with the ultraviolet light having a wavelength longer than 200 nm and having energy higher than binding energy of constituent molecules of the high-k dielectric film.