|A publication of the National Electronics Manufacturing Center of Excellence||December 2003|
Michael D. Frederickson
Often the inadvertent use of surrogate counterfeit components results in unexpected premature failure.
The Status of Electronic Product Counterfeiting
The EMPF’s failure analysis laboratory has witnessed first hand the effects of undisclosed material changes in chip capacitors, inductors and resistors (Figures 2-1 and 2-2). In one case, the removal of a specified nickel plated diffusion barrier at the inductor's terminals resulted in premature reliability problems. Cross sections of these components revealed separation of the solder from the side of the inductor. This separation was caused by the dissolution of the Ag plating layer into the solder. The vendor did not report the change in the terminal metallization until the customer received several units returned from the field. Without the diffusion barrier, the silver plated inductors were considered to be a high reliability risk for their intended environment. This change in the internal metallization could not be detected by the assembler's normal vendor qualification methods, inspection after assembly, or burn-in testing.
The production of bare circuit boards is not immune to the counterfeit issue. A number of circuit board assemblers and manufacturers have recently reported the use of substandard or unspecified materials in the fabrication of substrates, conductors, laminates, and surface finishes. The EMPF's failure analysis laboratory has observed an increase in the number of cases involving substandard printed wire board (PWB) manufacturing practices. The use of unspecified gold plating has recently come to the forefront of board solderability issues. Changes in laminate and substrate manufacturing have resulted in boards that have increased moisture sensitivity, decreased flexural rigidity, poor adhesive properties, and dielectric properties that are below specifications.
Of particular concern is the use of unspecified materials for the assembly of lead-free and leaded circuit cards. Concerns have grown about the formation of tin whiskers, lead-free material compatibility, and increased processing temperatures. With narrow process windows and ever increasing reliability concerns, the use of specified materials is paramount for improving the transition to environment friendly alloys. As manufacturers experiment with die attach materials and surface finishes, the changes in material specifications often outpace the developed product. These changes often go unnoticed until product failure occurs.
Effective Detection and Protective Measures
Standardized practices for identifying counterfeit and suspect components are not readily available to the public. However, many organizations have established internal procedures for identifying, quarantining, and reporting. Recent EMPF Helpline calls have brought to light that the methods for dealing with counterfeit and substandard components are not universal and may even involve techniques that affect component reliability.
Many leading OEMs and contractors are doing extensive testing to determine the overall quality of locally and internationally purchased parts. The Department of Energy (DOE) has their own recommended approach for the resolution of suspect counterfeit semiconductors through their procurement process. These practices are a combination of optical inspection, supplier tracking, physical and electrical testing, and record keeping . Other organizations utilize both procurement and performance based screening methods. Universally, components and PWBs should be quality screened and tested on a lot by lot basis.
2."Counterfeit Wave rises in the East", Electronic News Staff, 9/02 Electronic News
3."China Seen as Key to Counterfeiting Problem", Graham, J and Sullivan, L, Electronics Design News and Technology Network, http://www.edtn.com/story/biz/OEG20010216S0069-R
4. “Policy and Procedure for Controlling Suspect/ Counterfeit Items”, Ernest Orlando Lawrence Berkely National Laboratory,
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