circuitnet
Sponsor
kyzen

Electronic Assembly Cleaning Basics
Monitoring & effectively controlling chemistry concentration when cleaning electronic assemblies is crucial for maintaining optimal cleanliness results & preventing costly consequences.
KYZEN
Start Micro Dispensing Today
Sponsor
Indium-Corporation

Your award-winning cored wire supplier
As an industry-leading, full-line supplier of flux-cored wire solder, our award-winning solutions meet the needs of virtually every assembly and rework application.
Indium Corporation
Ask the Experts
INDEX
ASK
PANEL
JOIN
COMMENT
SEARCH
June 29, 2011 - Updated
June 27, 2011 - Originally Posted

ENIG and Black Pad



We have noticed a problem on ENIG boards in our WAVE process. The problem looks similar to Black Pad. We do not know how to identify the problem, or where to begin to find a resolution to the problem. Here are some facts:
  1. Black residue is on the vias and this on the solder side.
  2. Component side SMT parts do not exhibit the problem.
  3. Boards are processed Pb-free - SAC305, with no-clean water based flux.
  4. THTs will not wet after residues appear (for touch up process)
  5. Blowholes appear to accompany the defect but are not always present.
Hope you can help identify the problem and how to eliminate it.

G. R.

Expert Panel Responses

You likely have a sulfur contamination issue. Sulfur residues can occur when there is ineffective cleaning after the nickel plating process.

image
Dr. Craig D. Hillman
CEO & Managing Partner
DfR Solutions
Dr. Hillman's specialties include best practices in Design for Reliability, strategies for transitioning to Pb-free, supplier qualification, passive component technology and printed board failure mechanisms.
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 Comments



Free Newsletter Subscription
Circuitnet is built for professionals who bear the responsibility of looking ahead, imagining the future, and preparing for it.

Insert Your Email Address

Sponsor
Circuit-Technology-Center

Touchless Solder Ball Removal
Watch our video showcasing touch-free BGA component deballing. This revolutionary approach achieves unparalleled reliability and precision when preparing BGA components for re-balling.
Circuit Technology Center
ISM Storage and Software Integration Solutions