Sputtering target and production method therefor

Abstract

Provided is a sputtering target manufactured by die forging, characterized in that an average crystal grain size D at a portion where an average crystal grain size is the largest and an average crystal grain size d at a portion where an average crystal grain size is the smallest are related as 1.0<D/d<2.0. Further provided is a method capable of constantly manufacturing a sputtering target excellent in characteristics by improving and elaborating forging and heat treatment processes to render a crystal size fine and uniform, and a sputtering target excellent in quality obtained by this method.

1 : A sputtering target manufactured by die forging and having at least one three-dimensional stereoscopic hat or dome shaped structure in diametrical cross-section with an opening diameter and a depth, a ratio of said opening diameter and said depth being 1:3 or less, and an average crystal grain size D at a portion of said target where an average crystal grain size is largest and an average grain size d at a portion of said target where an average crystal grain size is smallest being related as 1.0<D/d<2.0.  
     
     
         2 : A sputtering target, comprising a hexagonal sputtering target manufactured by die forging and having a three-dimensional stereoscopic structure such as a hat or dome shape with an opening diameter and a depth, a ratio of said opening diameter and said depth being 1:3 or less, and said target having an erosion face with a total intensity ratio of a (002) face, and a (103) face, (014) face and (015) face within a 30° angle thereof is of 30% or more, and variation being within ±10% of an average value.  
     
     
         3 . (canceled).  
     
     
         4 : A method of manufacturing a sputtering target, comprising the steps of performing hot or cold kneading and straightening annealing to an ingot or billet material; adjusting crystal grains of the material by performing cold preforming and recrystallization annealing; thereafter performing die forging; and after said die forging step, performing straightening or recrystallization annealing.  
     
     
         5 : A method according to  claim 4 , wherein said sputtering target is a hexagonal sputtering target and has an erosion face with a total intensity ratio of a (002) face, and a (103) face, (014) face and (015) face within a 30° angle thereof of 30% or more, and variation is within ±10% of an average value.  
     
     
         6 - 16  (canceled).  
     
     
         17 : A sputtering target according to  claim 1 , wherein said target is made of a material selected from a group consisting of copper, titanium, aluminum, nickel, cobalt, tantalum, and alloys thereof.  
     
     
         18 : A sputtering target according to  claim 2 , wherein said sputtering target is made of titanium.  
     
     
         19 : A method according to  claim 5 , wherein said sputtering target is made of titanium.  
     
     
         20 : A method according to  claim 4 , wherein a total absolute value of true strain in said hot or cold kneading is 4 or more.  
     
     
         21 : A method according to  claim 20 , wherein said material has a melting point of Tm, and said die forging step is performed at a temperature of 0.5 Tm or less.  
     
     
         22 : A method according to  claim 21 , wherein said recrystallization annealing step performed after said cold preforming step and said straightening or recrystallization annealing step performed after said die forging step are performed at a temperature of 0.6 Tm or less.  
     
     
         23 : A method according to  claim 22 , wherein said cold preforming step is performed at a processing ratio of 20 to 90%.  
     
     
         24 : A method according to  claim 4 , wherein said material has a melting point of Tm and said die forging step is performed at a temperature of 0.5 Tm or less.  
     
     
         25 : A method according to  claim 4 , wherein said material has a melting point of Tm and said recrystallization annealing step performed after said cold preforming is performed at a temperature of 0.6 Tm or less.  
     
     
         26 : A method according to  claim 4 , wherein said material has a melting point of Tm and said straightening or recrystallization annealing step performed after said die forging step is performed at a temperature of 0.6 Tm or less.  
     
     
         27 : A method according to  claim 4 , wherein said cold preforming step is performed at a processing ratio of 20 to 90%.  
     
     
         28 : A method according to  claim 4 , wherein, as a result of performing recrystallization annealing after cold preforming, an average crystal grain size D 0  at a portion of said target where an average crystal grain size is largest and an average grain size d 0  at a portion of said target where an average crystal grain size is smallest are related as 1.0<D 0 /d 0 <1.5.  
     
     
         29 : A method according to  claim 4 , wherein, as a result of performing recrystallization annealing after cold preforming, a grain size of said material is 200% or less of an ultimate average crystal grain size of said target.  
     
     
         30 : A method according to  claim 4 , wherein, as a result of performing straightening or recrystallization annealing after die forging, an average crystal grain size of said target is in a range of 1 to 500 μm.  
     
     
         31 : A method according to  claim 4 , wherein an average crystal grain size D at a portion of said target where an average crystal grain size is largest and an average grain size d at a portion where an average crystal grain size is smallest are related as 1.0<D/d<2.0.  
     
     
         32 : A method according to  claim 4 , wherein said target is made of a material selected from a group consisting of copper, titanium, aluminum, nickel, cobalt, tantalum, and alloys thereof.