General Properties of CVD Diamond

 

Property Value
Hardness* 10,000 kg/mm2
Strength, tensile
>1.2 GPa
Sound velocity* 17,500 m/s
Density 3.52 g/cm3
Atom density* 1.77 x 1023 1/cm3
Young’s modulus* 1140 GPa
Poisson’s ratio 0.069
Thermal expansion coefficient 1.1 ppm/K
Thermal conductivity* 20.0 W/cmK
Debye temperature* 2,220 K
Refractive index 2.41
Optical transparency

UV to far IR
Loss tangent at 140 GHz < 10-5
Dielectric constant 5.7
Dielectric strength 10,000,000 V/cm
Electron mobility 2,200 cm2/Vs
Hole mobility 1,600 cm2/Vs
Bandgap 5.45 eV
Resistivity 1013 – 1016 Wcm
*highest value of all solid materials
Thermal properties Thermal conductivity
800-1800 w/mK, tailored to the application. Measured through-thickness at 20 degrees C.Thermal expansion
1.0 ppm/K at 20*C
1.6 ppm/K at 100*C
2.3 ppm/K at 200*C
3.5 ppm/K at 400*C
Mechanical properties Fracture strength
800 MPa at 200 um thickness
400 MPa at 800 um thickness
Optical properties Optical absorption
< 0.04 cm-1 (10.6 um)Optical scattering
< 0.8 % (633 nm, BDTF 2*-80*)
Dielectric properties Loss tangent
tan d = 1-2 10-5 at 140 GHz