FEATURES

• Medical Electronics Assembly
  ‘Checking Up’ on Medical Electronics
  Medical electronics assembly demands a different set of criteria than do commercial PCBs. The US FDA requires specific documentation, especially for verification of certain processes. Today’s medical electronics assembly also requires special testing, avoiding obsolete components and a detailed evaluation of a Pb-free product, as a looming EU RoHS Directive is expected to include medical electronics.
  By Zulki Khan

• Cover Story
  Solder Ball Attachment Using Laser Soldering
  Reballing BGAs due to rework and conversion from RoHS-compliant solders to SnPb (or vice-versa) typically requires subjecting the component to additional reflow cycles beyond component manufacturer recommendations. Laser attachment or laser reballing in an oxygen-free bath eliminates two additional temperature excursions and provides improved component reliability by facilitating the use of standard assembly reflow temperatures without mixed alloys.
  By Joshua Muonio and Richard Stadem

• Components
  Improving QFN Reliability
  The proper amount of solder is needed to ground the bottom of a QFN package and simultaneously create a toe fillet. Too much solder on the ground plane can cause parts to float; too little means insufficient grounding. This article focuses on the toe fillet and bottom connection, which create a kind of two-pronged connector, providing electrical continuity from both points.
  By Joseph G. Ameen and Gilson V. Geralde

FIRST PERSON

• Letters

• Caveat Lector
  Doing business, the standard way.
  Mike Buetow

• Talking Heads
  Design Chain Associates’ Mike Kirschner.
  Chelsey Drysdale

MONEY MATTERS

• Global Sourcing
  Outsourcing gets medieval.
  Charlie Barnhart

TECH TALK

• Screen Printing
  One size doesn’t fit all.
  Clive Ashmore

• Better Manufacturing
  A mask for all seasons.
  Phil Zarrow

• Reflow Soldering
  Optimal oven conditions.
  Ursula Marquez de Tino

• Tech Tips
  Reworking Pb-free PCBs.
  American Competitiveness Institute

• Test and Inspection
  ICT gets probed.
  Stacy Kalisz Johnson

• Process Doctor
  Cleaning becomes an event.
  Michael Bixenman

• Pb-Free Lessons Learned
  The tenacity of Pb-free residues.
  Chrys Shea

• Alternative Energies
  Adding solar cells to the SMT line.
  Darren Brown

• Eastern Advances (1.38 MB PDF in Chinese)
  Soldering terminations.
  Sanqiang Cai

• Technical Abstracts

DEPARTMENTS

Industry News
Market Watch
Product Spotlight
Ad Index
Assembly Insider

On the cover: A laser reballing process can cut two temperature excursions. (Photos courtesy General Dynamics)