TIN ELECTRODEPOSITS HAVING PROPERTIES OR CHARACTERISTICS THAT MINIMIZE TIN WHISKER GROWTH

摘要

A tin deposit which is inherently less prone to tin whisker formation or growth is obtained by one or more of: (i) the deposition of a fine-grained tin deposit having an average grain diameter in the range of 0.05 to 5 microns; (ii) a phosphorous compound in the solution that is used to electroplate the tin deposit so that that the deposit incorporates trace amounts of phosphorous which reduces tin whisker formation by preventing surface oxides even when exposed to heat or humidity; or (iii) a phosphorous, mercaptan or organic compound in a solution that applies a protective coating to the surface of a previously electroplated tin deposit, wherein the protective coating acts to minimize or prevent oxide formation or corrosion of the tin deposit during exposure to heat or humidity. Such tin deposits containing 80% to 100% by weight of tin exhibit minimal to no tin whisker growth.