Gallium nitride/sapphire thin film having reduced bending deformation
View Patent ↗The present invention relates to a gallium nitride/sapphire thin film, wherein a curvature radius thereof is positioned on the right side of a curve plotted from the following functional formula (I): Y=Y 0 +A·e −(x 1 −1)/T 1 +B ·(1− e −x 2 /T 2 ) (I) wherein Y is the curvature radius (m) of a gallium nitride/sapphire thin film, x 1 is the thickness (μm) of a gallium nitride layer, x 2 is the thickness (mm) of a sapphire substrate, Y 0 is −107±2.5, A is 24.13±0.50, B is 141±4.5, T 1 is 0.56±0.04, and T 2 is 0.265±0.5.
1. A gallium nitride/sapphire thin film, wherein a curvature radius thereof is positioned on the right side of a curve plotted from the following functional formula (I):
Y=Y 0 +A·e −(x 1 −1)/T 1 +B ·(1 −e −x 2 /T 2 ) (I)
wherein
Y is the curvature radius (m) of a gallium nitride/sapphire thin film,
x 1 is the thickness (μm) of a gallium nitride layer,
x 2 is the thickness (mm) of a sapphire substrate,
Y 0 is −107±2.5,
A is 24.13±0.50,
B is 141±4.5,
T 1 is 0.56±0.04, and
T 2 is 0.265±0.5.
2. The gallium nitride/sapphire thin film of claim 1 , wherein the curvature radius thereof is positioned on the left side of a curve plotted from the formula (I) when Y 0 is −293±2.5, A is 72.52±0.74, B is 372±4.5, T 1 is 1.15±0.04 and T 2 is 0.262±0.5.
3. The gallium nitride/sapphire thin film of claim 1 , wherein the curvature radius thereof is positioned on a curve plotted from the formula (I) when Y 0 is −293±2.5, A is 72.52±0.74, B is 372±4.5, T 1 is 1.15±0.04 and T 2 is 0.262±0.5.
4. The gallium nitride/sapphire thin film of claim 1 , which comprises an aluminum nitride (AlN) interface between the GaN, layer and the sapphire substrate in an embossed shape.
5. The gallium nitride/sapphire thin film of claim 4 , wherein the AlN interface is formed by treating the sapphire substrate successively with gaseous ammonia (NH 3 ), a gas mixture of hydrogen chloride (HCl) and ammonia and gaseous ammonia.
6. The gallium nitride/sapphire thin film of claim 5 , wherein a gas mixture of HCl and NH 3 has a mix ratio ranging 1:10 to 1:20 by volume.
7. The gallium nitride/sapphire thin film of claim 4 , wherein the AlN interface has embossings of a height of 150 nm or less and a traverse width of 10 to 100 nm in a density of 25 to 500 EA/μm 2 .
8. The gallium nitride/sapphire thin film of claim 1 , wherein the gallium nitride layer has a thickness of 0.5 to 20 μm.
9. The gallium nitride/sapphire thin film of claim 1 , wherein the gallium nitride layer has a thickness of 80 to 200 μm.
10. An optoelectronic or electronic device which comprises the gallium nitride/sapphire thin film of claim 1 as a substrate.
11. The optoelectronic or electronic device of claim 10 , which is a light emitting device.
12. A gallium nitride layer separated from the gallium nitride/sapphire thin film of claim 1 .
13. The gallium nitride layer of claim 12 , which has a thickness of 80 to 200 μm.