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Improving Global Quality of Life
Through Optimum Use and Innovation of Welding and Joining Technologies
The electronic products industry sector includes both consumer electronics and electronic devices that
are incorporated into other components, including medical devices, aerospace, automotive, and defence
products. The market is divided into applications such as consumer, communications, computer, industrial,
and automotive. The world electronic product market was $1.8 trillion in 2006 and was expected to increase
at a compound annual growth rate of 9.5% over the next five years.
Industrial products accounted for 39.6% of the sales in this market, and consumer electronics made up
13.4%.
Industry reports break down the consumer electronics market into four categories, computer,
personal communications, home media devices, and luxury devices. In a 2005 industry report published by
In-Stat the top three devices in terms of growth were portable digital audio players (57%), LCD televisions
(52.3%),
and DVD recorders (51.4%).
Rapid advances in computer and associated electronic systems can only be sustained
by advances in joining methods adapted to a miniature scale of operation. There
are six basic joining operations in the assembly of electronic products: package
fabrication, attachment and interconnection of active and passive components,
package sealing, package attachment and other devices to PCBs and the mounting
of electronics in a fabricated enclosure. The joining techniques commonly used for
these operations are shown below.
Welding is fundamental to the assembly and performance of electronic devices. For example, 25 µm-
diameter wire welds (thermosonic/ultrasonic) are used to interconnect silicon chips per year in excess of
5
trillion. In harsh environments (e.g. medical implants, chemically active or high temperature) the quality of
the package sealing weld (e.g. laser, electron beam) can directly influences the electronic device reliability
and life.
Thermosonic wire
bonded silicon chip
Table 9.1
Joining processes used in the electronics sector
Metal/ceramic package fabrication
Attachment of active or passive
components to substrate circuitry
Interconnections to solid state circuits
Package sealing
Attachment of packaged and other
devices to circuit boards
Fabricated enclosure
Brazing, Soldering, Resistance welding
Laser, electron beam and arc welding, Glass fusion
Soldering
Adhesive bonding
Thermosonic/Ultrasonic hot pressure welding
Soldering
Plastic encapsulation, Glass fusion
Resistance brazing, Resistance, laser and EB welding
Cold pressure welding, Soldering, Adhesive bonding
Soldering, Adhesive bonding
Resistance welding
Mechanical fastenings, Adhesives, Plastic and metal welding
Activity Joining process