THE EFFECT OF ELECTROPLATING PARAMETERS ON TIN “WHISKERS” FORMATION
Abstract
The article is devoted to the investigation of potential defects that can appear in thin-film electrochemical coatings based on tin, which do not contain lead, during their long storage. The purpose of the study is to develop technological regimes of electrolysis, which ensure minimization of the probability of the appearance such defects and reliable operation of radio electronic equipment The problems of tin and lead-free alloys based on it, as well as methods of elimination of such potential defects as the formation of “whiskers” are considered. To control the growth of “whiskers” in the post-electrolysis period (12 months of natural aging under laboratory conditions), a Sn-Bi coating was chosen, which was formed using both a constant and a pulse-reversed current. Based on the results which were obtained with scanning electron microscope, it was established that deposition of an alloy using pulsed and reverse current not only improves the structure of the coatings formed, but also significantly reduces the propensity to form whiskers, their length and density per unit area in comparison with coatings obtained with direct current. Possible reasons for achievement of high quality electrochemical coatings with Sn-Bi alloy have been established. The slowest growth of “whiskers” was obtained at reversed current with an average density i av= 2 A/dm2, frequency f = 1 Hz and duty ratio γ = 1.5.
About the Authors
V. K. Vasilets
Belarussian State University of Informatics and Radioelectronics
Belarus
Researcher, Research Laboratory “Functional electroplated systems”
Belarus
Researcher, Research Laboratory “Functional electroplated systems”
A. A. Khmyl
Belarussian State University of Informatics and Radioelectronics
Belarus
D. Sc. (Engineering), Research Laboratory “Functional electroplated systems”
Belarus
D. Sc. (Engineering), Research Laboratory “Functional electroplated systems”
L. K. Kushner
Belarussian State University of Informatics and Radioelectronics
Belarus
Senior Researcher, Research Laboratory “Functional electroplated systems”
Belarus
Senior Researcher, Research Laboratory “Functional electroplated systems”
I. I. Kuzmar
Belarussian State University of Informatics and Radioelectronics
Belarus
Ph. D. (Engineering), Research Laboratory “Functional electroplated systems”
Belarus
Ph. D. (Engineering), Research Laboratory “Functional electroplated systems”
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