2007 Volume 75 Issue 11 Pages 879-884
During the electrodeposition of a multilayer film, the thickness of each layer can be obtained accurately by controlling not only the potential but also the extent of the chemical reaction. The extent of the chemical reaction is usually controlled with the electrodeposition time. However, it is an approximate measure and not very precise. When a multilayer film is electrodeposited by the pulse potential technique, the fluctuation of current is unavoidable. Therefore, the deposition rate is unstable. As a solution to this problem, we have developed a “coulomb controller” that controls the quantity of electricity. The coulomb controller has been designed such that it can be used for monolayer electrodeposition. The circuit of the coulomb controller has been newly developed in order to detect the moment when the quantity of electricity reaches a target value. The coulomb controller has been assembled and used in a trial operation. The result of this operation has confirmed that the accuracy of the coulomb controller is suitable for the specification that is determined beforehand. Thus, it is confirmed that the coulomb controller can be installed in general electrochemical systems and can be used for monolayer electrodeposition.