A detailed study of scaling behavior in electrochemical etching of tungsten wires: Effects of non-uniform etching

• Published in: The Journal of physics and chemistry of solids Vol. 74; no. 1; pp. 30 - 34
• Main Authors: McDonnell, P., Graveson, T., Rackson, C., Kim, W.J.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.01.2013
• Subjects: A. Metals; A. Surface; B. Chemical synthesis; D. Defects; D. Electrochemical properties; Electric wire; Electrical resistance; Electrochemical etching; Etching; Exponents; Power law; Segments; Tungsten; B. Chemical synthesis; D. Electrochemical properties; A. Surface; D. Defects; A. Metals
• ISSN: 0022-3697; 1879-2553
• DOI: 10.1016/j.jpcs.2012.07.014

We report electrochemical etching of a tungsten wire and its scaling behavior based on electrical resistance measurements. The resistance curve exhibits a unique power law, and yet its scaling exponent is found to be smaller than that expected on the basis of Ohm's law. A simple numerical analysis aided by atomic force microscopy indicates that the observed exponent is possibly subject to spatial non-homogeneity that occurs during an etching process in which individual wire segments tend to approach their own singular points. Despite this non-uniform etching, a unique value of scaling factor 0.84±0.06 has been obtained, consistent with a previous result. ► We have performed electrochemical etching of tungsten wires. ► A slightly reduced scaling exponent is observed from electrical resistance measurements. ► Surface inhomogeneity is shown to be responsible for the reduced scaling exponent. ► Despite inhomogeneity, the obtained exponent is consistent with a previous study.