To demonstrate that
the probability of tin whisker induced short is increased by electrostatic
attraction which will cause the whisker to bend.
relay plated with pure tin was found to have a very long tin whisker
growing from the surface of its mounting tab. The mounting tab was
electrically grounded and a test probe tip was brought into close
proximity of the tin whisker. The probe tip was placed at an
electrical potential of 50 V relative to the tin whisker in order to
demonstrate the bending of the whisker due to electrostatic attraction.
The photograph shown below illustrates how the tin whisker is capable of
bending under the forces of electrostatic attraction. This
experiment was repeated hundreds of times with this same tin whisker
without causing the whisker to break loose from its base. This
experiment demonstrates that the likelihood of tin whisker induced shorts
is increased by electrostatic attraction.