-
- News
- Books
Featured Books
- pcb007 Magazine
Latest Issues
Current IssueThe Sustainability Issue
Sustainability is one of the most widely used terms in business today, especially for electronics and manufacturing but what does it mean to you? We explore the environmental, business, and economic impacts.
The Fabricator’s Guide to IPC APEX EXPO
This issue previews many of the important events taking place at this year's show and highlights some changes and opportunities. So, buckle up. We are counting down to IPC APEX EXPO 2024.
Getting to Know Your Designer
In this issue, we examine how fabs work with their design customers, educating them on the critical elements of fabrication needed to be successful, as well as the many tradeoffs involved. How well do you really know your customer? What makes for a closer, more synchronized working relationship?
- Articles
- Columns
Search Console
- Links
- Events
||| MENU - pcb007 Magazine
The Impact of Soldermask Processing on ENIG/ENEPIG Deposit Quality
September 17, 2013 |Estimated reading time: 1 minute
Soldermask (SM) is a permanent insulating coating designed to protect the PCB. The mask creates a barrier to contamination, corrosion and handling defects, and it also prevents solder bridging during assembly. The most common type in use today is a liquid photoimageable soldermask (LPISM). The successful application of SM involves multiple processing steps; following vendor recommendations and proper process control could preclude many problems downstream.
The ENIG/ENEPIG deposition also involves multiple processing steps that require the same attention to detail. For best results and the highest solder joint reliability, the product coming to the ENIG/ENEPIG line must have uncontaminated clean copper on which to plate, with perfectly defined and cured SM.
LPISM processing involves the following process steps:
- Surface pre-treatment;
- Application of LIPSM to PCB;.
- Evaporation of solvent (tack dry);
- UV photo exposure (imaging);
- Development of exposed board; and
- Thermal final cure.
Process control of the different steps involved in SM applications is paramount to the success of the ENIG/ENEPIG deposit. Out-of-control processing could lead to skip plating, and/or nickel corrosion; the former results in failure to deliver the desired nickel thickness and the later leads to problems with soldering and solder joint reliability.
The following is a discussion of each process step and its impact on the quality of the ENIG/ENEPIG deposit.Read the full column here.Editor's Note: This column was originally published in the July 20136 issue of The PCB Magazine.