Electronics Assembly Knowledge, Vision & Wisdom
Stencil Design for Ultra Fine Pitch Printing
Stencil Design for Ultra Fine Pitch Printing
Miniaturization is pushing the stencil printing process. As features become smaller, solder paste transfer efficiency is becoming more critical.
Production Floor

Production Floor programs cover topics including:
CAD/CAM/CIM/EDA, Circuit Board Handling, Clean Room, Cleaning Operations, Component Insertion, Component Prep, Dispensing, Feeders, Fume Extraction, Hand Tools, Labeling/Marking, Lasers, Material Handling, Odd Form, Ovens/Curing, Packaging, Stencil Printing, Repair/Rework, Soldering and more.
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 Comment



Authored By:
Mark Whitmore, Jeff Schake & Clive Ashmore
DEK Printing Machines Ltd
11 Albany Road, Weymouth
Dorset, DT4 9TH, UK

Summary
Miniaturization is pushing the stencil printing process. As features become smaller, solder paste transfer efficiency is becoming more critical.

In latest research work, actual paste deposit volumes and transfer efficiency have been monitored and compared for both square and round apertures with area ratio's ranging from 0.20 thru to 1.35. This covers apertures sizes of between 100 and 550 microns in a nominal 100 micron thick stencil foil. In addition, the effect of ultrasonically activated squeegees (ProActiv) has been assessed as part of the same experiment.

A further comparison has also been made between type 4 and type 4.5 solder paste as well. The data presented here will help provide guidelines for stencil aperture designs and strategies for ultra-fine pitch components such as 0.3CSP's.

Conclusions
The next generation of ultra fine pitch components will place extreme demands on the stencil printing process. The requirement for printing solder paste through stencil apertures with area ratios below 0.5 will become common place.

The data presented here indicates that with judicial choice of stencil design and materials it will be possible for designers to work with aperture area ratios down to 0.4. To optimise a process it is becoming increasingly important that an engineer has a good understanding of stencil aperture design specification, material properties and process options/aids available to him.

The interactions between all of these facets is becoming more complex and critical to the successful implementation of a process.

Initially Published in the SMTA Proceedings

Comments
No comments have been submitted to date.
Free Newsletter Subscription
Every issue of the Circuit Insight email newsletter will bring you the latest information on the issues affecting you and your company.

Insert Your Email Address

Directory Search


Program Search
Related Programs
bullet Step Stencil Setup
bullet An Introduction to the Process of Printed Electronics
bullet Innovative of CU Electroplating Process for Any Layer Via Fillwith Planer Via Top and Thin Surface Copper
bullet Top 5 BGA Rework Challenges to Overcome
bullet Should Apertures be Home Plate or Inverted Home Plate?
bullet Enabling High-Speed Printing Using Low Cost Materials
bullet Control of the Underfill of Surface Mount Assemblies
bullet Quantifying Stencil Aperture Wall Quality
bullet What Rate is World Class for SMT Machines?
bullet Fine Pitch Solder Joint Fuze Electronics Under Mechanical Shock Loads
More Related Programs