Abstract: In order to achieve a high control accuracy of the cylindrical microelectrode processing, the electrochemical etching technology for fabrication of microelectrode is researched in depth. In view of various shortcomings of single-stepped cylindrical microelectrode, the machining principle and the processing flow of the multi-stepped cylindrical microelectrode are analyzed. According to the three distinguishable strands during the etching process, the etching variety for each stage of the microelectrode is studied through mathematical formula, based on which the size and shape control functions of micro electrode are established. The invariability of the current density during the etching process is confirmed by the experiments, and the influence of different current density on the electrodes diameters is discussed. Then, the corresponding functions among the voltage, current density and immersion depth are built by the experimental results reduction, and at the same time, the correctness of electrode diameter changing linearly with machining time is verified. Based on the above two models, the mathematical control model for fabricating the multi-stepped cylindrical microelectrode is set up. It proves that the experimental and theoretical values have a good agreement by the experiment of a third-stepped microelectrode. A set of different multi-stepped cylindrical microelectrodes are fabricated under the guidance of the control model.

Key words: Current density, Cylindrical electrode, Electrodes diameter, Micro electrode, Multiple stepped, analogy design, Conceptual design, function analogy, functional similarity, TRIZ