Soldering Defects Database
| Title: | Satisfactory Lead-Free Joint on MELF Termination |
| Description: | Reflow joints on MELF terminations often do not have the volume of solder to meet the minimum inspection criteria; however, they are seldom rejected. The MELF has been reflow soldered using tin/silver/copper paste in a convection system. A satisfactory joint has been produced and the wetting line can be seen along the width of the termination. |
| Probable Cause: | As this is a satisfactory joint the only option is to add more solder if a problem does arise with the product in service. However, increasing the stencil thickness may lead to issues on other components. |
| Number of Defects: | 5 |
| Solder Alloy Option: | Lead-free |
| Defect Category: | Assembly/soldering |
| Defect Location: | Process |
| Product Volume: | Medium (10 to 50 per week) |
| Product Application: | Telecommunications |
| Solder joint on MELF: | |
| Soldering Processes: | |
| Possible Solution: | Reliability testing has been conducted at NPL on different terminations and with different volumes of solder. Joint reliability has also been modelled by computer and is covered in report.
For details contact Ling Zou email ling.zou@npl.co.uk Telephone 0208 943 6065 |
| Further Details: |