Oxide sintered body, sputtering target and oxide semiconductor film

Abstract

An oxide sintered body is characterized in that it comprises an oxide including an In element, a Zn element, a Sn element and a Y element and that a sintered body density is equal to or more than 100.00% of a theoretical density.

1 . An oxide sintered body comprising an oxide including an In element, a Zn element, a Sn element and a Y element, wherein the oxide sintered body is mainly composed of the bixbyite phase represented by In 2 O 3 . 
     
     
         2 . The oxide sintered body according to  claim 1 , wherein the proportion of presence of the bixbyite phase represented by In 2 O 3  in the oxide sintered body is equal to or more than 50 to 99 wt %. 
     
     
         3 . The oxide sintered body according to  claim 1 , wherein the three-point bending strength of the oxide sintered body is equal to or more than 120 MPa. 
     
     
         4 . The oxide sintered body according to  claim 1 , wherein the coefficient of linear expansion of the oxide sintered body is equal to or less than 8.0×10 −6 (K −1 ). 
     
     
         5 . The oxide sintered body according to  claim 1 , wherein the oxide sintered body includes an indium trizincoindate phase represented by In((Zn 3 In)O 6 ). 
     
     
         6 . The oxide sintered body according to  claim 1 , wherein the oxide sintered body density is equal to or more than 100.00% of a theoretical density. 
     
     
         7 . The oxide sintered body according to  claim 1 , wherein the oxide sintered body includes a pyrochlore phase represented by Y 2 Sn 2 O 7 . 
     
     
         8 . The oxide sintered body according to  claim 1 , wherein any one or more of the Y element and the Zn element form a substitutional solid solution with the bixbyite phase. 
     
     
         9 . The oxide sintered body according to  claim 1 , wherein atomic ratios of the Zn element, the Y element, the Sn element and the In element are within the following ranges:
   0.01≤Zn/(In+Zn+Y+Sn)≤0.25,
     0.03≤Y/(In+Zn+Y+Sn)≤0.25,
     0.03≤Sn/(In+Zn+Y+Sn)≤0.30, and
     0.20≤In/(In+Zn+Y+Sn)≤0.93.
   
     
     
         10 . The oxide sintered body according to  claim 1 , wherein atomic ratios of the Zn element and the In element are within ranges below, and
 the sintered oxide body includes no spinel phase represented by Zn 2 SnO 4 ,
   0.01≤Zn/(In+Zn+Y+Sn)≤0.25
 
   0.50≤In/(In+Zn+Y+Sn)
 
   
     
     
         11 . The oxide sintered body according to  claim 10 , wherein the oxide sintered body includes a pyrochlore phase represented by Y 2 Sn 2 O 7 . 
     
     
         12 . The oxide sintered body according to  claim 11 , wherein any one or more of the Y element and the Zn element form a substitutional solid solution with the bixbyite phase. 
     
     
         13 . The oxide sintered body according to  claim 10 , wherein atomic ratios of the Y element and the Sn element are within the following ranges:
   0.03≤Y/(In+Zn+Y+Sn)≤0.25, and
     0.03≤Sn/(In+Zn+Y+Sn)≤0.30.
   
     
     
         14 . The oxide sintered body according to  claim 1 , wherein atomic ratios of the Zn element and the In element are within ranges below, wherein
 the oxide sintered body consists of a bixbyite phase represented by In 2 O 3  and a pyrochlore phase represented by Y 2 Sn 2 O 7 , or   the oxide sintered body consists of a bixbyite phase represented by In 2 O 3 , a pyrochlore phase represented by Y 2 Sn 2 O 7  and an indium trizincoindate phase represented by In((Zn 3 In)O 6 ),
   0.01≤Zn/(In+Zn+Y+Sn)≤0.25
 
   0.50≤In/(In+Zn+Y+Sn)
 
   
     
     
         15 . The oxide sintered body according to  claim 14 , wherein any one or more of the Y element and the Zn element form a substitutional solid solution with the bixbyite phase. 
     
     
         16 . The oxide sintered body according to  claim 14 , wherein atomic ratios of the Y element and the Sn element are within the following ranges:
   0.03≤Y/(In+Zn+Y+Sn)≤0.25, and
     0.03≤Sn/(In+Zn+Y+Sn)≤0.30.
   
     
     
         17 . A sputtering target comprising the oxide sintered body according to  claim 1 . 
     
     
         18 . An oxide semiconductor film formed by sputtering a sputtering target according to  claim 1 . 
     
     
         19 . The oxide semiconductor film according to  claim 18 , wherein the oxide semiconductor film is amorphous. 
     
     
         20 . A thin-film transistor comprising the oxide semiconductor film according to  claim 18 .