The Effect of Electrolytic Deflash Current on Delamination of Epoxy Mold Compound During Tin Plating Process

In the electroplating process of acidic tin-plating in laboratory, temperature is required to control at 5 °C or so, but conditions of the laboratory is limited, the average temperature is above 5 °C, which leads to Sn2+ in the bath hydrolyze, produce Sn(OH)2 impurities, and part of Sn2+ in the anode oxidize to produce metastannic acid. As time goes by, impurities increase gradually and eventually lead to the bath not be recycled. This paper mainly studied on impurities in the waste after electroplating were synthesized after a series of oxidation, filter and reduction, which makes recycled materials recycled to the greatest extent, non-recycling materials buried deep after high-temperature incineration. After the experiment, stannous oxide and distilled water in the waste get recycled, and the purity of stannous oxide gotten recycled is above 99.5%, which can be reused.

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Research on tin whisker growth of pure tin plating of different lead substrates

Proceedings of the 20th IEEE International Symposium on the Physical and Failure Analysis of Integrated Circuits (IPFA) ◽

10.1109/ipfa.2013.6599235 ◽

2013 ◽

Author(s):

Zhou Bin ◽

Wan Zhonghua ◽

Li Xunping ◽

En Yun-fei

Keyword(s):

Whisker Growth ◽

Tin Whisker ◽

Tin Plating

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An investigation of tin whisker growth over a 32-year period

Circuit World ◽

10.1108/cw-07-2015-0038 ◽

2016 ◽

Vol 42 (4) ◽

pp. 183-196 ◽

Cited By ~ 4

Author(s):

Mark Andrew Ashworth ◽

Barrie Dunn

Keyword(s):

Cross Sections ◽

Whisker Growth ◽

Tin Whisker ◽

Content Type ◽

Intermetallic Formation ◽

Time Period ◽

Whisker Length ◽

Electron Microscopy Analysis ◽

Long Time ◽

Tin Plating

Purpose This paper aims to present the results of a 32-year-old laboratory study of whisker growth from tin electrodeposits that was originally undertaken to gain an increased understanding of the phenomenon of tin whisker growth. Design/methodology/approach Whisker growth was evaluated using electroplated C-rings (both stressed and un-stressed) that were stored throughout in a desiccator at room temperature. Analysis has recently been undertaken to evaluate whisker growth and intermetallic growth after 32 years of storage. Scanning electron microscopy analysis has been performed to investigate whisker length and, using polished cross-sections, the morphology, thickness and type of intermetallic formation. Findings Normal tin-plated deposits on brass and steel with a copper barrier layer nucleated whiskers within five months, and in each case, these grew to lengths between 1 and 4.5 mm. For normal tin electroplated onto brass, a one- or two-month nucleation period was needed before whiskers developed. They reached a maximum length of about 1.5 mm after six months, and little or no further growth occurred during the subsequent 32 years. Very few whiskers grew on the tin-plated steel samples and no intermetallic formation was observed. None of the fused tin plating samples nucleated whiskers during the 32-year period. Practical implications Knowledge about vintage whiskers is important to take steps to increase the resiliency of space missions. Similarly, such knowledge is important to engineers engaged in products reaching their nominal end-of-life, but where, for reasons of economy, these products cannot be replaced. Originality/value This study represents a unique insight into whisker growth and intermetallic formation over an extremely long time period.

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