By Peter Weiss
Three satellites have gone dead because of whiskers. Last spring, a whisker shut down a Connecticut nuclear power plant. The culprits aren’t errant facial hairs: They’re metal filaments that spontaneously sprout from electroplated metal films in electronic devices, where they can short out circuits. By tracking properties of such films for up to a year, researchers have now learned more about the films’ internal stresses, which are suspected of causing whisker growth.
The whisker problem largely disappeared in the 1960s with the introduction of lead-tin films in electronics. Researchers had found that metal combination to be almost immune to the problem. But a worldwide drive to eliminate lead from electronics products has resurrected the menace. The European Union, for instance, begins its electronics-lead ban next summer.