Substrate Material Properties 2017-03-23T14:49:37+00:00

Substrate Material Properties

The substrate is the foundation on which the thin film components are built. The substrate properties have significant influence on the performance of the device. Alumina is still the most common substrate material due to its surface quality, cost, and high frequency performance.

As fired 96% Alumina
CLA Surface Roughness (µ-inches) = 35
Thickness Available (inches) .010-.120
Dissipation Factor at 1 MHz 0.0004
Dielectric Constant (k) 9.5
Thermal Conductivity (W/mK) 26
Coefficient of Thermal Exp. (ppm/°C) 6.3-8.0 (25-1000°C)
Applications Low to medium power DC & RF circuits
As fired 99.6% Alumina
CLA Surface Roughness (µ-inches) 4
Thickness Available (inches) .005-.040
Dissipation Factor at 1 MHz 0.0001
Dielectric Constant (k) 9.9
Thermal Conductivity (W/mK) 30
Coefficient of Thermal Exp. (ppm/°C) 7.0-8.3 (25-1000°C)
Applications Low to medium power DC & RF circuits
Polished 99.6% Alumina
CLA Surface Roughness (µ-inches) 2
Thickness Available (inches) .004-.040
Dissipation Factor at 1 MHz 0.0001
Dielectric Constant (k) 9.9
Thermal Conductivity (W/mK) 30
Coefficient of Thermal Exp. (ppm/°C) 7.0-8.3 (25-1000°C)
Applications Low to medium power RF and Microwave circuits
Lapped Aluminum Nitride
CLA Surface Roughness (µ-inches) 25
Thickness Available (inches) .004-.120
Dissipation Factor at 1 MHz 0.001
Dielectric Constant (k) 8.6
Thermal Conductivity (W/mK) 170 min
Coefficient of Thermal Exp. (ppm/°C) 4.6 at (25-300°C)
Applications High power DC/RF/microwave circuits
Polished Aluminum Nitride
CLA Surface Roughness (µ-inches) 3
Thickness Available (inches) .004-.080
Dissipation Factor at 1 MHz 0.0005
Dielectric Constant (k) 8.6
Thermal Conductivity (W/mK) 170 min
Coefficient of Thermal Exp. (ppm/°C) 4.6 (25-300°C)
Applications High power DC/RF/microwave circuits
Polished 99.5% Beryllium-Oxide
CLA Surface Roughness (µ-inches) 3
Thickness Available (inches) .007-.080
Dissipation Factor at 1 MHz 0.0004
Dielectric Constant (k) 6.5
Thermal Conductivity (W/mK) 250 min
Coefficient of Thermal Exp. (ppm/°C) 6.4-8.6 (25-1000°C)
Applications High power DC/RF/microwave circuits
Ferrite/Garnet
CLA Surface Roughness (µ-inches) 4 – 40
Thickness Available (inches) .010 and up
Dissipation Factor at 1 MHz .00015 – .0025
Dielectric Constant (k) 9.0 – 15.5
Thermal Conductivity (W/mK) .7 – 4.5
Coefficient of Thermal Exp. (ppm/°C) 2.4 – 10.8
Applications Microwave, circulators, isolators, components
Borosilicate Glass
CLA Surface Roughness (µ-inches) 3.9×10-8
Thickness Available (inches) 0.7mm – 25.4mm
Dissipation Factor at 1 MHz .00037
Dielectric Constant (k) 4
Thermal Conductivity (W/mK) 1.2
Coefficient of Thermal Exp. (ppm/°C) 3.25 (through 300°C)
Applications Optical windows, biomedical
Sapphire
CLA Surface Roughness (µ-inches) .1
Thickness Available (inches) .003-.250
Dissipation Factor at 1 MHz 0.00086/0.0003
Dielectric Constant (k) 9.3-11.4
Thermal Conductivity (W/mK) 40
Coefficient of Thermal Exp. (ppm/°C) A plane at 25°C 5.3
Applications Optical
Polished Fused Silica/Z-Cut Quartz
CLA Surface Roughness (µ-inches) .1
Thickness Available (inches) .003-.040
Dissipation Factor at 1 MHz 0.000015
Dielectric Constant (k) 3.8
Thermal Conductivity (W/mK) 1.4
Coefficient of Thermal Exp. (ppm/°C) 0.56
Applications High frequency circuits requiring extremely low loss performance
Silicon
CLA Surface Roughness (µ-inches) 7.8 x 10-7
Thickness Available (inches) .25mm – .5mm
Dissipation Factor at 1 MHz .005
Dielectric Constant (k) 11.8
Thermal Conductivity (W/mK) 125
Coefficient of Thermal Exp. (ppm/°C) 2.5
Applications Optical, medical, IR, sensors, components
Polished Titanates
CLA Surface Roughness (µ-inches) 3
Thickness Available (inches) .005-.080
Dissipation Factor at 1 MHz 0.0004
Dielectric Constant (k) 38-200
Thermal Conductivity (W/mK) 1.8-4.2
Coefficient of Thermal Exp. (ppm/°C) 5.8
Applications RF & microwave circuits requiring high Q