Introduction
II-VI Infrared introduces a new line of chemical vapor deposition (CVD) diamond substrates for the infrared optics market. With over 20 years of experience in producing CVD zinc selenide (ZnSe) and zinc sulfide (ZnS), II-VI has developed high-quality CVD diamond materials tailored for optical applications.

Material Properties
Physical Properties: The CVD diamond substrates have a cubic, polycrystalline structure with a density of 3.51 g/cm³. Electrical density and dielectric constant details are available upon consultation with technical staff.
Optical Properties: The bulk absorption coefficient at 10.6 µm is 0.12/cm, and the refractive index is 2.38. The temperature change of the refractive index at 10.6 µm is 9.6 x 10^-6/°C.
Thermal Properties: Thermal conductivity at 20°C is 20 W/cm•K, specific heat is 0.509 J/g°C, and the linear expansion coefficient at 20°C is 1.0 x 10^-6/°C.
Mechanical Properties: Young’s modulus is 1220 GPa, rupture modulus ranges from 200-1000 MPa, Knoop hardness is 85-100 GPa, Poisson’s ratio is 0.10-0.29, and fracture toughness is 5-7 MPa√m.

Applications
CVD diamond substrates are used in CO2 laser windows for high-power industrial lasers, high-power microwave windows for gyrotrons, fusion reactors, radar, and directed energy weapons, and thermal management as heat sinks.

Unique Properties
The substrates are extremely hard, scratch-resistant, have the highest thermal conductivity (five times better than copper), low thermal expansion coefficient, resistant to thermal shock, transparent over a wide range from deep UV to far infrared and microwave, chemically inert, durable, and biocompatible.

Data Summary
Thermal Conductivity: Varies with temperature, from 2190 W/m K at 0°C to 700 W/m K at 500°C.
Index of Refraction: Ranges from 2.722 at 0.22 µm to 2.380 at 25.2 µm.
Transmission: The transmission percentage varies with wavelength, indicating high transparency across a broad spectrum.

Contact Information
II-VI Infrared has worldwide sales offices in China, Singapore, Japan, UK, Switzerland, Belgium, USA, Germany, and Italy. Contact details for each location are provided for placing orders or inquiries.