Advancing Manufacturing Technology

Characterize and Quantify the Production Inspection Capability of the AXI of HiP (Head in Pillow) Defects



Call for Participation Webinar

Statement of Work and Project Statement


HiP (Head in Pillow) solder joint defects have a greater risk of occurrence with increasing BGA package size (modules/CPU sockets), thicker boards (increased layers) and non-complimentary warpage characteristics.

In addition, HiP defect Detection with in-line AXI (Automatic X-ray Inspection) equipment is a high risk FMEA (Failure Modes and Effects Analysis) element where algorithms used are not proven to be robust enough leading to:

  • High probability of false passes (algorithm based)
  • High probability of false passes (operator over rides) – Training/Shade of Gray scale resolution and defect determination.

Current algorithms are based on simplistic models (supplied by X-ray equipment manufacturers) and are composed on differently generated X-ray images such as Transmissive, Laminography, and Tomosysnthesis techniques. This leads to correlation inconsistencies and subsequent low Agreement Analysis (kappa value less than 0.7).

Limited electrical coverage test (ICT/FCT) post AXI in process becomes a reliability concern when released to the field for (e.g., enterprise server systems, other high-reliability applications). In addition, there is a lack of “golden” sample with various HiP defects for calibration and correlation.  As a result, a need exists to quantify and correlate HiP defects across all AXI equipments’ algorithms and levels of HiP conditions.

Purpose of Project

A pre-competitive investigation to characterize and quantify production inspection capability of the AXI of HiP (Head in Pillow) defects.

Steps for Joining the Project
Please note:  iNEMI membership is required to sign up for this project.  Initial sign-up for this project ended on Sepember 29, 2016.  New sign-ups must be approved by the project team.  Steps for joining the project follow.

For iNEMI members:
  • Complete and sign the project statement
  • Fax the completed statement(s) to +1 (703) 834-2735 or scan and email to
For non-members:

For Additional Information

David Godlewski