measure surface resistivity

Discussion in 'The Projects Forum' started by rijinca, Feb 23, 2010.

  1. rijinca

    Thread Starter New Member

    Feb 23, 2010
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    how to measure surface resistivity using 4 point probe methord?
    anyone?
     
  2. KL7AJ

    AAC Fanatic!

    Nov 4, 2008
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    Attach two probes near outer surface of material under test.. Apply a source voltage to these. Between these two probes, attach the sensor probes. Measure the voltage differential betwen the two sensor probes.

    You need to know the surface area, and the spacing between the probes. I've got the actual formula somewhere. Stand by.!

    Eric
     
  3. MikeML

    AAC Fanatic!

    Oct 2, 2009
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    I vaguely recall that you force a current between the outer probes, and measure the voltage between the inner probes. The geometry factors out as long as the probes are colinear and equally spaced.
     
  4. JoeJester

    AAC Fanatic!

    Apr 26, 2005
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