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NanoFab Tool: Mercury Probe

Mercury Probe

Mercury Probe

The Four Dimensions CV92A mercury probe system provides non-destructive and rapid measurement of current-voltage and capacitance-voltage curves to derive resistivity, breakdown voltage/field and film thickness of thin dielectric films without having to metallize the wafer and fabricate capacitors, as is required by traditional probe stations. The capacitor top contact (”gate”) is simply formed by a mercury contact. The accuracy of the measurements is guaranteed by the precisely defined contact area. Other parameters such as doping density profiles, trap distribution, pinhole/defect density, charge/capacitance versus time, charge versus voltage and dielectric constant can be easily derived as well. The system has a user-friendly software that offers comprehensive maps of up to 200 points per wafer.


  • Capacitance range: 0 to 20 nF
  • Frequency range: DC to 10 MHz
  • Current range: 50 fA to 1 mA
  • Bias voltage range: -1000 V to +1000 V
  • Mercury dot contact area: 4x10-4 cm2 and 2x 10-2 cm2
  • A dot-ring contact is available for use with insulating substrates
  • Sample size: 1 cm x 1 cm to 200 mm diameter wafer
  • Sample thickness: 100 μm to 2.0 mm
  • Wafer mapping: polar, cartesian and user-defined
  • Safety: the mercury contact comes from below and does not leave any residue on the wafer

Typical Applications

  • Resistance and resistivity
  • Capacitance
  • Breakdown voltage
  • Charge at breakdown
  • Oxide thickness
  • Dielectric constant
  • Charge density
  • Interface trap distribution
  • Leakage current
  • Carrier lifetime
  • Pinhole density
Created March 5, 2018, Updated June 15, 2023