INFICON SID-242 Thin Film Deposition Controller - Manual (Page 95)

Appendix
Z-Factor is used to match the acoustic properties of the material being deposited to the
acoustic properties of the base quartz material of the sensor crystal. Z-Factor is the
ratio of the acoustic impedance of the sensor to that of the deposited material.
If you know the acoustic impedance of your material, it is easy to calculate the Z-Factor.
The sensor is basically silicon dioxide, and has an acoustic impedance of 8.83. For
example, Gold has an acoustic impedance of 23.18, so:
Gold ZFactor = 8.83/23.18 = .381