Gallium containing zinc oxide

1. A gallium containing zinc oxide, which has a heat ray shielding function, a gallium content in the range of 0.25 to 25% by weight, and a carrier electron density n e of 2×10 20 / cm 3 or higher, and which further contains an element having a covalent bond radius different from that of zinc atom in the same content or lower than the content of the gallium.

2. The gallium containing zinc oxide according to claim 1 , wherein a carrier electron mobility μ is in the range of 0.1 to 40 cm 2 /Vs.

3. The gallium containing zinc oxide according to claim 1 , wherein the carrier electron density n e and the carrier electron mobility μ satisfy μ≦3.75 n e ×10 −20 .

4. The gallium containing zinc oxide according to claim 1 , wherein the carrier electron density n e and the carrier electron mobility μ satisfy 0.2≦(n e ×10 −20 /μ) and a solar transmission Ts and a visible light transmission Tv satisfy Tv/Ts≧1.0.

5. The gallium containing zinc oxide according to claim 1 , wherein the element having a covalent bond radius different from that of zinc atom is an element having a tetra-coordination ion radius in the range of 0.4 to 0.95 nm except gallium.

6. The gallium containing zinc oxide according to claim 1 , wherein the element having a covalent bond radius different from that of zinc atom is an element of Group XIII elements or Group XIV elements except gallium.

7. The gallium containing zinc oxide according to claim 1 , wherein the element having a covalent bond radius different from that of zinc atom is fluorine element or chlorine element.

8. A gallium containing zinc oxide thin film, which comprises the gallium containing zinc oxide according to claim 1 , and has a film thickness of 5 μm or thinner, the solar transmission Ts and the visible light transmission Tv satisfying Ts≦1.4 Tv−39.

9. The gallium containing zinc oxide thin film according to claim 8 , which has a film thickness of 5000 nm or thinner, and the visible light transmission Tv of 70% or higher and/or the transmission of 70% or higher for light rays with wavelength of 500 nm.

10. The gallium containing zinc oxide thin film according to claim 8 , wherein the solar transmission Ts and the visible light transmission Tv satisfy Ts≦1.4 Tv−44 in the case the film thickness is in the range of 30 to 350 nm.

11. The gallium containing zinc oxide thin film according to claim 8 , wherein the solar transmission Ts and the visible light transmission Tv satisfy Ts≦1.4 Tv−54 in the case the film thickness is in the range of 350 to 5000 mm.

12. The gallium containing zinc oxide thin film according to claim 8 , wherein the transmission for light rays with wavelength of 750 mm is 88% or lower.

13. The gallium containing zinc oxide thin film according to claim 12 , wherein the transmission for light rays with wavelength of 750 nm is 75% or lower.

14. The gallium containing zinc oxide thin film according to claim 8 , wherein the transmission for light rays with wavelength of 1000 mm is 80% or lower.

15. The gallium containing zinc oxide thin film according to claim 14 , wherein the transmission for light rays with wavelength of 1000 nm is 60% or lower.

16. The gallium containing zinc oxide thin film according to claim 8 , wherein the transmission for light rays with wavelength of 1200 mm is 65% or lower.

17. The gallium containing zinc oxide thin film according to claim 16 , wherein the transmission for light rays with wavelength of 1200 mm is 35% or lower.

18. The gallium containing zinc oxide thin film according to claim 8 , wherein the transmission for light rays with wavelength of 1500 nm is 40% or lower.

19. The gallium containing zinc oxide thin film according to claim 18 , wherein the transmission for light rays with wavelength of 1500 mm is 15% or lower.