Tin Whisker Growth: Substrate Effect Understanding CTE Mismatch and IMC Formation

摘要

This work demonstrated that substrates have significant influence on whisker growth propensity depending on aging or whisker test conditions. A Ni barrier layer is very effective in eliminating tin whisker growth under isothermal conditions by eliminating the driving force, that is, compressive stress generated by IMCs. However, this Ni barrier layer will not eliminate the thermal stress generated during temperature cycling due to CTE mismatch. Consequently, it is not necessarily a panacea for eliminating whisker growth.