Properties of sapphire substrate and sapphire wafers
Typical Properties of Sapphire Wafers and Substrates
Sapphire is a single crystal Al2O3 with a hexagonal (rhombohedral) crystal structure. Sapphire wafers and
sapphire substrates are available in C, R, A and M plane orientations.
Sapphire related services include, Sapphire wafer back-thinning, edge grinding, edge rounding, diameter reduction, hole drilling, chamfering, blending and polishing, v-grooves, surface pyramid structures, laser slag removal, slots and steps.
Technical Data Sheet
| Name |
Orientation |
| C-Plane (0 Degree) |
0001 |
| R-Plane |
1-102 |
| A-Plane (Perpendicular to C) |
11-20 |
| M-Plane (Perpendicular to C and A) |
|
| Mechanical Properties |
|
| Density at 20°C |
3.98 g/cm3 |
| Hardness |
Knoop: 1500
Mohs: 9 |
| Tensile Strength |
275 – 400 MPa
40,000 – 58,000 psi |
| Flexural Strength |
480 – 895 MPa
70,000 – 130,000 psi |
| Compression Strength (ultimate) |
2.0 GPa / 300,000 psi |
| Young’s Modulus (elasticity) |
345 GPa / 50 x 106 psi |
| Bulk Modulus (compression) |
250 GPa / 36 x 106 psi |
| Shear Modulus (rigidity) |
145 GPa / 21 x 106 psi |
| Modulus of Rupture |
350 – 690 MPa / 50,000 – 100,000 psi |
| Poisson’s Ratio |
.29 |
| Melting Point |
2040°C / 3700°F / 2310 K |
|
|
| Thermal Properties |
|
| Thermal Conductivity: |
|
| Perpendicular to C |
at 23°C: 23.0 W/m°C
at 77°C: 16.8 W/m°C |
| Parallel to C |
at 24°C: 25.8 W/m°C
at 70°C: 17.35 W/m°C |
| Specific Heat |
at 18°C: 756 J/kg°C
at -182°C: 104 J/kg°C |
|
|
| Electrical Properties |
| Volume Resistivity |
at 25°C 1014 ohm/cm |
| Dielectric Strength |
4.8 x 105 |
| Dielectric Constant: |
|
| Perpendicular to C |
9.4 |
| Parallel to C |
11.5 |
| Dissipation Factor |
10-4tan δ |
CTE (Coefficient of Thermal Expansion),
x 106/ °C |
| Temp °C |
Perpendicular to C |
Parallel to C |
| 70 |
6.95 |
5.90 |
| 100 |
7.08 |
6.05 |
| 200 |
7.66 |
6.60 |
| 300 |
8.30 |
7.32 |
| 400 |
9.00 |
8.07 |
| 500 |
9.63 |
8.88 |
| 600 |
10.45 |
9.77 |
Related Sapphire Web pages: