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Tech Seconds: How to Eliminate Head-in-Pillow (HIP) Defects

  • Head In Pillow
  • Indium Corporation
  • Videos

  • Indium Corporation’s Tech Seconds video series features Phil Zarrow answering the electronics assembly industry’s most commonly asked questions... in less than 60 seconds. In this installment, Phil describes how to diagnose defects caused by head-in-pillow (HIP).

    Question: Phil, I've been running into a lot of intermittent failures at functional test. I think it's head-in-pillow. What should I do?

    Phil Zarrow: To mitigate head-in-pillow, there's a number of things you can try. First of all, you want to make sure that you get a proper solder deposition. In other words, that the geometries of your apertures on your stencil are appropriate for what you're trying to put down. Second, you want to look at your profile. You want to make sure that your time-above-liquidus, as well as a soak if you're using it, are not excessive in that they're exhausting the flux formulation. And last, but certainly not least, you want to ensure that your reflow profile is compatible with the solder paste formulation that you're using. And remember, we're all in this together.