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Tech Seconds: How to Troubleshoot 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 examines the best methods used to troubleshoot head-in-pillow (HIP) defects.

    Question: Hey, Phil. I've been having some issues with head-in-pillow lately. What are the top three things I should look for when I start troubleshooting?

    Phil Zarrow: Start with your solder paste deposits. Are you getting the insufficient deposit? Are you getting the right release from your apertures? Are your apertures on your stencil designed properly? Another factor would be the component placement. Is it properly located, in terms of the X, Y, theta, and Z axes? And finally, look at your profile, especially the soak time. Look at the soak zone and the time above liquids to ensure that they're not excessive, and that they're compliant with the solder paste formulation that you're using.

    Question: What are the best methods to identify head-in-pillow defect?

    Phil Zarrow: Of course, we want to avoid destructive testing, so probably the most widely used methodology would be oblique angle X-ray. A CT scan is also used, particularly in FA labs. And finally, last but not least, if you happen to have one still kicking around, X-ray laminography can also be useful in determining head-in-pillow.