Semiconductor device, method of manufacturing semiconductor device, and substrate processing apparatus

Abstract

Provided is a semiconductor device including a metal film which can be formed with lower costs but still mange to have a necessary work function and oxidation resistance. The semiconductor device includes an insulating film disposed on a substrate; and a metal film disposed adjacent to the insulating film. The metal film includes a stacked structure of a first metal film and a second metal film. The oxidation resistance of the first metal film is greater than that of the second metal film. The second metal film has a work function greater than 4.8 eV and is different from the first metal film in material. The first metal film is disposed between the second metal film and the insulating film.

1 . A semiconductor device comprising:
 an insulating film disposed on a substrate; and   a metal film disposed adjacent to the insulating film,   wherein the metal film comprises a stacked structure of a first metal film and a second metal film,   an oxidation resistance of the first metal film is greater than that of the second metal film,   the second metal film has a work function greater than 4.8 eV and is different from the first metal film in material, and   the first metal film is disposed between the second metal film and the insulating film.   
     
     
         2 . The semiconductor device of  claim 1 , wherein the metal film is disposed on the insulating film, and further comprises the first metal film disposed on an outermost surface thereof. 
     
     
         3 . The semiconductor device of  claim 1 , wherein the stacked structure is repeatedly stacked in the metal film. 
     
     
         4 . The semiconductor device of  claim 1 , wherein a thickness of the first metal film ranges from 0.2 nm to 4 nm. 
     
     
         5 . The semiconductor device of  claim 1 , wherein a thickness of the second metal film ranges from 0.5 nm to 10 nm. 
     
     
         6 . The semiconductor device of  claim 1 , wherein a thickness of the second metal film ranges from 4 nm to 5 nm. 
     
     
         7 . The semiconductor device of  claim 1 , wherein the second metal film is thicker than the first metal film. 
     
     
         8 . The semiconductor device of  claim 1 , wherein the first metal film comprises one of a titanium nitride film, a tantalum nitride film, a titanium aluminum nitride film, and a tantalum aluminum nitride film. 
     
     
         9 . The semiconductor device of  claim 1 , wherein the second metal film comprises a non-noble metal. 
     
     
         10 . The semiconductor device of  claim 1 , wherein the second metal film comprises at least one of a nickel film, a cobalt film, a beryllium film, a carbon film, a selenium film, a tellurium film and a rhenium film. 
     
     
         11 . The semiconductor device of  claim 1 , wherein the insulating film comprises a high permittivity film. 
     
     
         12 . The semiconductor device of  claim 1 , wherein the insulating film comprises at least one of a hafnium oxide film, a zirconium oxide film, a hafnium oxide film doped with an aluminum, a zirconium oxide film doped with the aluminum, a titanium oxide film, a niobium oxide film, a tantalum oxide film, a strontium titanate film, a barium strontium titanate film and a lead zirconate titanate film. 
     
     
         13 . A method of manufacturing a semiconductor device, the method comprising:
 forming an insulating film on a substrate; and   forming a metal film comprising a stacked structure of a first metal film and a second metal film adjacent to the insulating film, the first metal film being formed between the second metal film and the insulating film,   wherein an oxidation resistance of the first metal film is greater than that of the second metal film, and   the second metal film has a work function greater than 4.8 eV and is different from the first metal film in material.   
     
     
         14 . A substrate processing apparatus comprising:
 a process chamber configured to process a substrate;   a first process gas supply system configured to supply a first process gas into the process chamber to form a first metal film;   a second process gas supply system configured to supply a second process gas into the process chamber to form a second metal film; and   a controller configured to control the first process gas supply system and the second process gas supply system,   wherein an oxidation resistance of the first metal film is greater than that of the second metal film,   the second metal film has a work function greater than 4.8 eV and is different from the first metal film in material, and   the controller controls the first process gas supply system and the second process gas supply system to form a metal film having a stacked structure of the first metal film and the second metal film adjacent to an insulating film disposed on the substrate by supplying the first process gas and the second process gas into the process chamber where the substrate is accommodated such that the first metal film is formed between the second metal film and the insulating film.