Coulometric coating thickness measurement technique

The coulometric coating thickness measurement technique is a precise method for determining the thickness of coatings on surfaces. This technique is based on the principle of electrolysis, in which the amount of material deposited by electrolysis is directly related to the thickness of the coating.

In this method, the surface to be measured is placed as a cathode in an electrolytic cell. A defined volume of a suitable electrolyte solution is used, and the area of the coating to be measured serves as the anode. The application of an electrical voltage triggers an electrolytic process that causes metal ions to migrate from the coating to the cathode, where they are electrochemically reduced.

The amount of metal deposited during this process can be precisely quantified by measuring the transferred charge (coulombs). This charge transfer is directly related to the thickness of the coating on the surface. Therefore, the coulometric coating thickness measurement method allows an accurate and direct determination of the coating thickness without relying on indirect calibrations or reference measurements.

This method is used in various industries, including electronics production, automotive and materials science. It offers the advantage of high accuracy and reproducibility in the determination of coating thicknesses, especially for thin coatings, which are critical for many applications.