Electronics Assembly Knowledge, Vision & Wisdom
Low Temperature SMT Solder Evaluation
Low Temperature SMT Solder Evaluation
Recent advances in alloy "doping" have opened the door to revisit Sn/Bi alloys as a possible alternative to SAC-305 for many applications.
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:
Howard "Rusty" Osgood, David Geiger, Robert Pennings, Christian Biederman, Jie Jiang, Jon Bernal
Flextronics International
Milpitas, CA, USA

The electronics industry could benefit greatly from using a reliable, manufacturable, reduced temperature, SMT solder material (alloy-composition) which is cost competitive with traditional Sn3Ag0.5Cu (SAC305) solder. The many possible advantages and some disadvantages / challenges are discussed.

Until recently, the use of Sn/Bi based materials has been investigated with negative consequences for high strain rate (drop-shock) applications and thus, these alloys have been avoided. Recent advances in alloy "doping" have opened the door to revisit Sn/Bi alloys as a possible alternative to SAC-305 for many applications.

We tested the manufacturability and reliability of three low-temperature and one SAC-305 (used as a control) solder paste materials. Two of these materials are doped Sn/Bi/Ag and one is just Sn/Bi/Ag1%.

We will discuss the tests and related results. And lastly, we will discuss the prospects, applications and possible implications (based on this evaluation) of these materials together with future actions.

Preliminary results investigating the low temperature paste alloys against the Sn3Ag0.5Cu paste alloy look promising. Limited internal testing to date, combined with limited external testing data, indicates that these newer, doped, lower temperature solders perform as well or better than Sn3AgCu(SAC305).

Further testing and evaluation is needed and is underway. We are proceeding with drop/shock and higher strain rate monotonic bend testing which is where we expect to see differentiation between the doped and non-doped solders under investigation.

Initially Published in the SMTA Proceedings

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 Has My Flux Expired?
bullet Nanocopper Based Paste for Solid Copper Via Fill
bullet Voiding/Drop Test for Mixed Alloy BGA Assembly
bullet New-Generation, Low-Temperature Lead-Free Solder
bullet Backward Compatible Solder Joint Reliability Under Accelerated Conditions
bullet Reliability of No-clean and Water-soluble Solder Pastes
bullet Predicting Fatigue of Solder Joints
bullet New-Generation, Low-Temperature Lead-Free Solder for SMT Assembly
bullet Low Temperature SMT Solder Evaluation
bullet Characterization of Solder Pastes Based on Two Alternative Alloys
More Related Programs