Electronics Assembly Knowledge, Vision & Wisdom
Process Control of Ionic Contamination in Assembly of Electronic Circuits
Process Control of Ionic Contamination in Assembly of Electronic Circuits
This paper reviews a testing protocol based on IPC-TM 650 2.3.25 to enable monitoring of ionic contamination within series production.
Analysis Lab

Analysis Lab programs cover topics including:
Corrosion, Contamination, Data Acquisition, ESD and EOS, Inspection, Measurement, Profiling, Reliability, R&D, RFID, Solder Defects, Test, Tombstoning, X-ray and more.
Submit A Comment
Comments are reviewed prior to posting. You must include your full name to have your comments posted. We will not post your email address.

Your Name

Your Company

Your E-mail

Your Country

Your Comment

Authored By:
P. Eckold, L. Henneken, R. Fritsch, U. Welzel
Robert Bosch GmbH, Automotive Electronics, Stuttgart, Germany

M. Routley, G. Naisbitt
Gen3 Systems Limited, Farnborough, UK

This paper reviews a newly developed testing protocol based on IPC-TM 650 2.3.25, established to enable monitoring of ionic contamination within series production.

The testing procedure was successfully implemented within the production of high reliability, safety critical electronic circuits, involving multiple production sites around the world. I will be shown in this paper that the test protocol is capable for meeting Six-Sigma-Criteria.

For a Gauge R&R study, a calibration solution of 0.1 wt.-% NaCl was used in order to investigate the repeatability and reproducibility of the test protocol employing newly developed contamination testing systems, which were placed at five locations worldwide. A total failure range of below 0.1 micrograms/cm squared congruent to NaCl at a target value of 1.0 micrograms/cm squared congruent to NaCl (plus or minus 8.8%) was achieved, combined with manual laboratory handling of fluids (pipette, temperature).

For process control this value is acceptable and demonstrates that ionic contamination testing based on IPC-TM 650 2.3.25 is able to be used as a process control tool in manufacturing of electronic control units.

As previously emphasised, electrochemical migration is caused by an electric field and a closed water film between neighbouring conductive paths. Ionic contamination is given by materials and processes and can accelerate the electrochemical processes under high temperature and high humidity conditions. Consequently, the measurement of ionic contamination does not predict the humidity reliability of printed board assemblies. The humidity robustness of design elements can be ensured by SIR measurement technology according to the principle of IPC 9202.

The implementation of ionic contamination testing as process control tool (PICT) exhibits advantages to current ROSE test protocols. Due to system optimization and the implementation of unified work place instructions, it was possible to achieve 6σ criteria for the repeatability and a sufficient reproducibility of recorded ionic contamination data at five different production sites worldwide. Using this approach, process control and methods of process optimizations are possible.

Initially Published in the IPC Proceedings

No comments have been submitted to date.
Free Newsletter Subscription
Every issue of the Circuit Insight email newsletter will bring you the latest information on the issues affecting you and your company.

Insert Your Email Address

Directory Search

Program Search
Related Programs
bullet Can High Particle Concentrations Impact PCB Assembly?
bullet Collaboration to Combat Head on Pillowing Defects
bullet Can Water Contamination Cause Failure?
bullet OEM and EMS to Combat Head on Pillowing Defects
bullet Novel Approaches for Minimizing Pad Cratering
bullet Head in Pillow Explained
bullet Tin Whisker Testing and Modeling
bullet Surface Mount Warpage Case Study
bullet Innovative BGA Defect Detection Method for Transient Discontinuity
bullet Acceptable Rate for Head in Pillow?
More Related Programs