Al2O3 Substrate (Sapphire)
Al2O3 crystal or Sapphire is a multi-function crystal materials with excellent properties: good thermos-stability, high thermal conductivity, high hardness, high transmission at infrared wavelength rang and excellent chemical stability. Sapphire is widely used in industrial, defense and security and scientific research fields. sapphire is also an important substrate materials for high temperature superconductivity applications, it can be used for film growth of Y-series, La-series, and it is also used to grow the superconductivity film of MgB2.
Features
1 ) Good thermos-stability
2 ) High thermal conductivity
3 ) High hardness
Applications
1 ) High temperature superconductivity film
2 ) IR window
Specifications
Materials | Al2O3 (Sapphire) | |
Orientation | A-plane | <11-20> |
R-plane | <1-102> | |
M-plane | <10-10> | |
C-plane | <0001> | |
Orientation Tolerance | ±0.5° | |
Surface Finish | Single side polished (SSP) or Double sides polished (DSP) | |
Polished Side Roughness | < 0.5 nm | |
Typical Size | 10 x 10 x 0.5 mm, φ50.8 x 0.5 mm, φ100 x 0.65 mm etc. | |
Dimension Tolerance | ±0.1 mm or better | |
Thickness Tolerance | ±0.05 mm or better | |
Maximum Size | Diameter 180 mm | |
Properties
Chemical Formula | Al2O3 | ||
Crystal Structure | M6 | ||
Lattice Parameters | a = 4.758 Å c =12.99 Å | ||
Crystal Purity | > 99.99% | ||
Melting Point | 2040 ℃ | ||
Density | 3.97 g/cm3 | ||
Hardness | 9 Mohs | ||
Thermal Expansion Coefficient (/ ℃) | 7.5 × 10^-6 | ||
Thermal Conductivity (Calorie/℃ Cm.S) | ⊥c | //c | |
23 ℃ | 0.055 | 26 ℃ 0.060 | |
77 ℃ | 0.040 | 70 ℃ 0.041 | |
Dielectric Constants | ~ 9.4 @300K at A axis ~ 11.58 @300K at C axis | ||