Sep 10, 2008 Currently, there are no set criteria for minimum lead free solder finish requirements. Many companies who have run this solder coating process in the tin-lead version know that thickness varies dramatically based on pad size. Furthermore, minimum coating thickness is more critical to the solderability of SN100CL more than it is to standard tin-lead finish. Combining these two facts, it is all the more important to create a new standard by pad area.
After studying literally thousands of panels and the subsequent solderability results, Saturn Electronics Corporation has established a coupon and general guidelines for this finish.
Having this coupon on the actual board / array removes the variation in acceptability measurements between the supplier and the customer by standardizing not only the location of the measurement, but also the thickness by applicable pad geometry.
Also, customers can request a gerber format of this coupon to the waste area of ther boards. Additionally, Saturn will send the suggested minimum thickness requirements resulting from the study.
Visit the SN100CL Minimum Thickness Guidelines page at: http://www.saturnelectronics.com/minimumguides.htm
If you have any further inquiries, contact Saturn Electronics Corp. to speak with an engineer regarding any further technical matters.
