Sputtering Target and Oxide Semiconductor Film

Abstract

A sputtering target containing oxides of indium (In), gallium (Ga) and zinc (Zn), which includes a compound shown by ZnGa 2 O 4 and a compound shown by InGaZnO 4 .

1 .- 23 . (canceled) 
     
     
         24 . A method for DC sputtering which comprises subjecting a sputtering target to DC sputtering to produce an oxide semiconductor film:
 wherein the sputtering target comprises a compound shown by InGaZnO 4  as a main component, which further contains a metal element with an atomic valency of positive tetravalency or higher,   wherein the content of the metal element with an atomic valency of positive tetravalency or higher is 100 ppm to 10000 ppm relative to the total metal elements in the sputtering target, and   wherein the sputtering target has a bulk resistance of less than 5×10 −3  Ωcm.   
     
     
         25 . The method according to  claim 24 , wherein the content of the metal element with an atomic valency of positive tetravalency or higher in the sputtering target is 200 ppm to 5000 ppm relative to the total metal elements in the sputtering target. 
     
     
         26 . The method according to  claim 24 , wherein the content of the metal element with an atomic valency of positive tetravalency or higher in the sputtering target is 500 ppm to 2000 ppm relative to the total metal elements in the sputtering target. 
     
     
         27 . The method according to  claim 24 , wherein the sputtering target has a bulk resistance of less than 2×10 −3  Ωcm. 
     
     
         28 . The method according to  claim 24 , wherein the sputtering target has a bulk resistance of less than 1×10 −3  Ωcm. 
     
     
         29 . The method according to  claim 24 , wherein the metal element with an atomic valency of positive tetravalency or higher in the sputtering target is at least one element selected from the group consisting of tin, zirconium, germanium, cerium, niobium, tantalum, molybdenum and tungsten. 
     
     
         30 . The method according to  claim 24 , wherein the metal element with an atomic valency of positive tetravalency or higher in the sputtering target is at least one element selected from the group consisting of tin, cerium and zirconium. 
     
     
         31 . The method according to  claim 24 , wherein the presence of no structure other than InGaZnO 4  in the sputtering target is confirmed by the X-ray diffraction analysis, or, if a structure other than InGaZnO 4  in the sputtering target is confirmed by the X-ray diffraction analysis, the intensity thereof is smaller than that of InGaZnO 4 . 
     
     
         32 . The method according to  claim 24 , wherein the sputtering target has a sintered body density of 6.0 g/cm 3  or more.