NSF Young Investigator: The Use of Electrohydrodynamic Impedance Spectroscopy for Characterization of Anodic Films

9358380 WEST这是对作为研究阳极形成膜的手段的电动力学(EHD)阻抗谱的关键评估。第二个目标是建立电抛光的机理。用交流电法和交流阻抗法研究了铜在浓磷酸和中性盐电解液中的电化学抛光过程。已有研究表明，在中性盐电解液中进行电抛光时，电极表面会形成盐膜。这些薄膜的电学性质是用交流阻抗确定的，而电学性质随薄膜生长的瞬时变化是由EHD阻抗监测的，这导致了对薄膜结构性质和导电机制的推断。相反，当金属在浓缩酸中进行电抛光时，是否会形成固体膜，这一点已经确定。这是通过EHD阻抗进行检测的，它还可以测试电抛光的替代机制。该研究结果直接适用于电子和半导体行业生产过程的监测和控制。

9358380 West This is a critical evaluation of electrodrodynamic (EHD) impedance spectroscopy as a means of investigating anodically formed films. A second objective is to establish the mechanisms of electropolishing. Alternating - current (AC) and EHD impedance spectroscopy methods are used to study the electropolishing of copper in concentrated phosphoric acid and in a neutral-salt electrolyte. It has been shown previously that a salt film forms on the electrode surface during electropolishing in neutral-salt electrolyte. The electrical properties of these films are determined with AC impedance, and transient changes in electrical properties with film growth are monitored by EHD impedance; this leads to inferences about structural properties and mechanisms of conduction in the films. In contrast, it has been established whether a solid film is formed when metals are electropolished in concentrate acids. This is examined with EHD impedance, which can also test alternatives mechanisms for electropolishing. The result of this research are directly applicable to monitoring and control of production processes used in the electronics and semiconductor industries.