Surface treatment method, shower head, processing container, and processing apparatus using them

Abstract

The method of the present invention includes: a first blasting step of carrying out blasting of the surface of a metal base material, such as a shower head or a processing container, by using a blasting material composed of a non-sublimable material (e.g. alumina); and a second blasting step of carrying out blasting of the surface of the metal base material, which has undergone the first blasting step, by using a blasting material composed of a sublimable material (e.g. dry ice). The first blasting step properly roughens the surface of the metal base material so that a film, which adheres to the surface during film-forming processing, hardly peels off. In addition, the second blasting step almost fully removes the residual non-sublimable blasting material adhering to the surface of the metal base material, thereby preventing the generation of particles deriving from the residual non-sublimable blasting material falling off the metal base material.

1 . A method of surface treatment in making a shower head, said method comprising:
 providing a shower head having a gas jet surface in which a plurality of gas jet holes are formed;   carrying out first blasting of the gas jet surface by using a non-sublimable blasting material composed of a non-sublimable material in such a manner that first areas of the gas jet surface around the gas jet holes are subjected to the first blasting while second areas of the gas jet surface, between adjacent gas jet holes outside the first areas, are not subjected to the first blasting; and   after the first blasting, carrying out second blasting of the gas jet surface by using a sublimable blasting material composed of a sublimable material.   
     
     
         2 . The method according to  claim 1 , further comprising cleaning the surface of the metal base material after the second blasting step. 
     
     
         3 . The method according to  claim 1 , wherein the non-sublimable blasting material is a material selected from the group consisting of a ceramic material, a resin, a metal oxide and quartz. 
     
     
         4 . The method according to  claim 1 , wherein the non-sublimable blasting material is a ceramic material selected from alumina (Al 2 O 3 ), aluminum nitride (AlN), silicon nitride (SiN) and silicon carbide (SiC). 
     
     
         5 . The method according to  claim 1 , wherein the non-sublimable blasting material is a metal oxide which is ZrO 2  or TiO 2 . 
     
     
         6 . The method according to  claim 1 , wherein the sublimable blasting material is dry ice. 
     
     
         7 - 10 . (canceled) 
     
     
         11 . A shower head having a gas jet surface in which a plurality of gas jet holes are formed, and which gas jet surface has undergone a first blasting by using a non-sublimable blasting material composed of a non-sublimable material in such a manner that first areas of the gas jet surface around the gas jet holes are subjected to the first blasting while second areas of the gas jet surface, between adjacent gas jet holes outside the first areas, are not subjected to the first blasting, and after the first blasting, a second blasting by using a sublimable blasting material composed of a sublimable material to provide micro irregularities in the first areas and thereby increase the surface area of the first areas. 
     
     
         12 . (canceled) 
     
     
         13 . A processing apparatus for performing predetermined processing of a processing object, comprising:
 a processing container for containing a processing object therein;   a shower head having a gas jet surface in which a plurality of gas jet holes are formed, and which gas jet surface has undergone a first blasting by using a non-sublimable blasting material composed of a non-sublimable material in such a manner that first areas of the gas jet surface around the gas jet holes are subjected to the first blasting while second areas of the gas jet surface, between adjacent gas jet holes outside the first areas, are not subjected to the first blasting, and after the first blasting, a second blasting by using a sublimable blasting material composed of a sublimable material to provide micro irregularities in the first areas and thereby increase the surface area of the first areas;   a high-frequency power source for applying a high-frequency power to the shower head;   a stage, for placing the processing object thereon, provided in the processing container; and   an exhaust system for evacuating the atmosphere in the processing container.   
     
     
         14 . The method according to  claim 1 , wherein, in the second blasting, the first areas are subjected to the second blasting while the second areas are not subjected to the second blasting. 
     
     
         15 . The method according to  claim 1 , wherein, in the second blasting, both the first and second areas are subjected to the second blasting. 
     
     
         16 . The method according to  claim 1 , wherein the first blasting is carried out with the second areas being covered with a mask having holes corresponding to the first areas. 
     
     
         17 . The method according to  claim 1 , wherein the second blasting is carried out with the second areas being covered with a mask having holes corresponding to the first areas.