Oxide sintered compact, oxide sputtering target, and oxide thin film
A sintered compact essentially consisting of zinc (Zn), gallium (Ga), silicon (Si) and oxygen (O), wherein a Zn content expressed in terms of ZnO is 5 to 60 mol %, a Ga content expressed in terms of Ga 2 O 3 is 8.5 to 90 mol %, and a Si content expressed in terms of SiO 2 is 0 to 45 mol %, and the sintered compact satisfies a condition of A≤(B+2C) when the Zn content expressed in terms of ZnO is A (mol %), the Ga content expressed in terms of Ga 2 O 3 is B (mol %), and the Si content expressed in terms of SiO 2 is C (mol %), and has a relative density of 90% or higher. An object of this invention is to efficiently obtain an amorphous film having high transmissivity and a low refractive index without having to introduce oxygen into the atmosphere during film deposition by DC sputtering.
1. A sintered compact consisting essentially of zinc (Zn), gallium (Ga), silicon (Si) and oxygen (O), wherein a Zn content expressed in terms of ZnO is 5 to 60 mol %, a Ga content expressed in terms of Ga 2 O 3 is 8.5 to 90 mol %, and a Si content expressed in terms of SiO 2 is 0 to 45 mol %, and the sintered compact satisfies a condition of A≤(B+2C) when the Zn content expressed in terms of ZnO is A (mol %), the Ga content expressed in terms of Ga 2 O 3 is B (mol %), and the Si content expressed in tends of SiO 2 is C (mol %), and has a relative density of 90% or higher.
2. The sintered compact according to claim 1 , wherein an atomic ratio of Zn and Ga satisfies a condition of Ga/(Ga+Zn)>0.21.
3. The sintered compact according to claim 2 , wherein the sintered compact has a diffraction peak attributed to ZnGa 2 O 4 in an X-ray diffraction.
4. The sintered compact according to claim 3 , wherein a volume resistivity measured with a constant current application method is 50 kΩ⋅cm or more.
5. The sintered compact according to claim 4 , wherein the relative density is 95% or higher.
6. The sintered compact according to claim 5 , wherein a L* value is 65 or more.
7. A sputtering target made from the sintered compact according to claim 1 .
8. The sputtering target according to claim 7 , wherein the volume resistivity measured with the constant voltage application method upon applying a voltage of 1 V is 1×10 6 Ωcm or more.
9. The sputtering target according to claim 7 , wherein the volume resistivity measured with the constant voltage application method upon applying a voltage of 500 V is 1/100 or less relative to the volume resistivity measured with the constant voltage application method upon applying a voltage of 1 V.
10. The sintered compact according to claim 1 , wherein the sintered compact has a diffraction peak attributed to ZnGa 2 O 4 in an X-ray diffraction.
11. The sintered compact according to claim 1 , wherein a volume resistivity measured with a constant current application method is 50 kΩ⋅cm or more.
12. The sintered compact according to claim 1 , wherein the relative density is 95% or higher.
13. The sintered compact according to claim 1 , wherein a L* value is 65 or more.
14. A thin film consisting essentially of zinc (Zn), gallium (Ga), silicon (Si) and oxygen (O), wherein a Zn content expressed in terms of ZnO is 5 to 60 mol %, a Ga content expressed in terms of Ga 2 O 3 is 8.5 to 90 mol %, and a Si content expressed in terms of SiO 2 is 0 to 45 mol %, and the thin film satisfies a condition of A≤(B+2C) when the Zn content expressed in terms of ZnO is A (mol %), the Ga content expressed in terms of Ga 2 O 3 is B (mol %), and the Si content expressed in terms of SiO 2 is C (mol %).
15. The thin film according to claim 14 , wherein a refractive index at a wavelength of 633nm is 1.95 or less.
16. The thin film according to claim 15 , wherein an extinction coefficient at a wavelength of 405 nm is 0.05 or less.
17. The thin film according to claim 16 , wherein the thin film is amorphous.
18. The thin film according to claim 17 , wherein the thin film is produced by being deposited via sputtering in an inert gas atmosphere without oxygen introduction.
19. The thin film according to claim 14 , wherein an extinction coefficient at a wavelength of 405 nm is 0.05 or less.
20. The thin film according to claim 14 , wherein the thin film is amorphous.