Large size Sapphire crystals up to 4" in boule are available from CASIX. As the hardest of oxide crystals, sapphire has a combination of optical and physical properties that make it the best choice for a variety of demanding applications. Sapphire maintains its strength even at high temperatures. It has good thermal properties, excellent electrical and dielectric properties and is resistant to chemical attack. These properties encourage the use of sapphire in aggressive environments where reliability, optical transmission and strength are required.
Main applications include: UV and IR Optics; Windows for High Temperature and Pressure, Corrosion Resistance, Abrasion Resistance; Heat Sinkers and Thermocouplers; Semiconductor Wafer Carriers; Electrical Insulators; Thin Film Deposition; Transparent Electronic Substrate; Silicon on Sapphire Wafers; Superconductor Substrate.
1. Basic Properties of Sapphire Crystal
Crystal Structure |
Hexagonal System |
Lattice |
a=4.785 Å, c=12.991 Å |
Density |
3.98 g/cm3 |
Transmission Range |
0.15 - 5.5 µm |
Melting Point |
2040 oC |
Specific Heat |
0.418 W· s /g /K |
Thermal Conductivity |
25.12 W /m /K (@ 100 oC) |
Thermal Shock Resistance |
790 W /m |
Thermal Expansion Coefficient |
5.8x10-6 /K |
dn / dT (@ 633 nm) |
13x10-6 /K |
Mohs Hardness: |
9 |
Refractive Index (no) |
1.83 (0.26 mm), 1.76 (0.63mm), 1.58 (5.57mm) |
2. Standard Specifications of Sapphire Windows & Mirrors
Diameter |
+0.0, -0.1 mm |
Thickness |
+/-0.2 mm |
Flatness |
better than l per 25 mm ( @ 633 nm ) |
Parallelism |
better than 3' |
Perpendicularity |
better than 5' |
Scratch-Dig |
80-50 per MIL-O-13830A |
Wavefront Distortion |
Less than l/2 per inch (l @ 1064 nm) |
Other high-precision Sapphire windows, AR- and HR-coatings are available upon request. Sapphire boule grown by CZ method and as-cut Sapphire blocks are also available.
opyright 1998 CASIX, Inc. All rights reserved.
Last Revised: May 19, 1999
Web Page maintained by : Contact@CASIX.com
 |
 |
 |
 |
 |