An appropriate way to measure the conductivity of
CLEVIOS™ is to deposit the material as a thin and homogeneous layer on a flat substrate by using deposition techniques such as spin-coating or doctor-blading. The thickness of the layers should be in the range of 50 - 500nm. The layer thickness can be determined by scratching the film off the substrate with a razor blade and scanning the stylus of a mechanical or optical profile meter across the scratch. The sheet resistance can then be measured with conventional four-point probes (van der Pauw).
Alternatively, the sheet resistance can be determined with a multimeter by measuring the impedance between parallel contacts. The contacts can be deposited onto the CLEVIOS™ layer for example with silver paint or by evaporating metals through a shadow mask. In case of simple two-point measurements the resistance of lead-in wires and contacts have to be negligible.
The resistance of high ohmic CLEVIOS™ P OLED-Types (CLEVIOS™ P AI4083 and CLEVIOS™ P CH8000) have to be measured in dry atmosphere, i.e. in a vacuum chamber or in a glove box filled with N2 or Ar to avoid the influence of humidity. In case of CLEVIOS™ P CH8000 spacing between metallic contacts should be small relative to the length ( b << a), otherwise the resistance will become too large to be measured properly.
