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Head in Pillow Causes & Process Solutions

Presenter: Bob Willis
Company: Bobwillisonline.com
Date Published: 2/5/2014

Description: Overview:
Open circuit and intermittent defects are the worst problem an engineer has to face in manufacture, difficult to find and often a problem to get to the root cause. The increasing use of area array packages and package on package assembly combined with lead-free processes has highlighted a new defect type referred to as head in, or head on pillow. We explain the problem, process parameters and ways of eliminating this type of defect during assembly.

This type of failure is not unique to lead-free or area array components we have been experiencing a similar problem in the past with fine pitch packages which will also be illustrated during Bob's webtorial.

Topics Covered:

  • What is Hip and Hop
  • Same defect type on surface mount
  • Solder sphere oxide
  • Solder sphere and package wetting tests
  • Reducing void formation in reflow
  • PCB/Component Package Warpage
  • Solder paste exhaustion
  • Reflow profile correction
  • Test methods and simulations
  • Pry testing
  • Inspection optically and with x-ray

    Who Will Benefit:
    This webtorial is designed for design, process and quality engineers responsible for eliminating reflow rejects like head on or in pillow. Much of the material presented is extremely visual and practical making it ideal for manufacturing staff, like all the instructors training it not just theory, it's a "How to Do It Session based on practical experience."

    Instructor Bio:
    Bob Willis currently operates training and consultancy business based in England and has created one of the largest collections of interactive training material in the industry. With his online training webinar's Bob has provided a cost effective solution to training worldwide and regularly runs training for SMTA, SMART, IPC and recently EIPC. Although a specialist for companies implementing lead-free manufacture Mr Willis has provided worldwide consultancy in most areas of electronic manufacture over the last 25 years. This is based on working in manufacture with contract assembly, printed board manufacture and environmental test facilities. This has earned him the SOLDERTEC/Tin Technology Global Lead-Free Award for his contribution to the industry. He has also been presented with the SMTA International Leadership Award and IPC Committee Award for contribution to their standards activity.

  • Key Words: 

    HiP, HoP, Head-in-Pillow, Head-on-Pillow,

      Members: $200.00 (Log on to receive the member rate)
      Non-Members: $300.00

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