TOKYO – JPCA 2007, while held in the middle of a slowdown in the electronics interconnect industry, must be considered an unqualified success. Between the innovations on display, the incorporation of the Protec assembly show, and real world collaboration, JPCA demonstrated the possibilities of realizing technical advances, and building the foundations for growth while maintaining profitability.
There were fewer than 200 Westerners in attendance at a show that was
packed for all three days. As the Western industry flails, the East
rises.
Overall, the printed circuit fabrication industry has continued its
consolidation. While sales revenues and volumes grow, resources and
technology are concentrating in fewer hands, and margins decrease as
technology matures. There is much greater focus on “bang for the buck."
Booth sizes for many exhibitors were shrunk and fewer systems were
displayed. However, that which was exhibited hinted at the still
amazing possibilities of an industry fundamental to modern
society. It’s not getting any easier, but the technologies are
available, whether in high density interconnect, embedded components,
or yield and process improvement. I saw examples of 30 micron lines and spaces; stacked
and staggered vias, embedded actives and passive components; all in production in products used everyday all over the world.
Starting with laminates, dimensional stability is improving; lower
dielectric constants, thermal resistance, and compatibility with
extended chemical and mechanical stress are all at the forefront.
Several papers during the technical program, and emphasis
on the show floor, were on reducing copper foil thickness along with
surface preparation for ultra-fine-line applications.
In drilling,
resistance to cracking during laser drilling, 200,000 rpm spindles
becoming a standard, and the ability to drill higher stacks with better
feeds and speeds are all part of a dynamic improvement in performance.
Drill room monitoring has become standard at many companies. The
ability to use real-time measurement of feeds, speeds, and drill wander
improves yields and productivity considerably, with several
manufacturers offering the technology.
In photoresists, the drive toward finer lines with improved sidewall
quality has shown incremental improvements. Dry-film remains standard in Japan, but
several suppliers exhibited roller coaters and other liquid
photoresist application technologies. In imaging, the emphasis
was on hybrid direct imaging systems, with several manufacturers
demonstrating conventional lamp technology based systems with the
ability to write directly at production speeds with the benefits of
scaling and artwork elimination. Interested in laser-based direct
imaging systems was also strong. Remember: many
Japanese PCB manufacturers have for years achieved high yields
on fine lines. Today’s bleeding edge is 15 micron
geometries. 50-75 micron lines and spaces are considered standard, with
electrical tests yields in the low-to-mid 90th percentile.
One interesting development in the layup process is to use prepreg as a
rigidizer in certain designs.
The variety and scope of designs and
technologies is truly amazing. Perhaps a dozen HDI processes, some
proprietary, most collaborative, are helping the Japanese interconnect
industry extend its dominance. Reduction in the real estate footprint,
reduced trace lengths, better pad adhesion, superior heat dissipation,
and reduced cost/functionality are all part of the package.
Indeed, there is a
misconception in the West as to applications utilizing HDI. A recent
flow chart by Matt Aoki published in the
Printed Circuit Journal listed the
usual cellular, handheld, digital camera, and other consumer
applications. HDI is gaining significant market share in
Japan in notebook computer, automotive navigation systems, workstation,
broadcasting equipment and telecom base station products. Constructions
include 1-2-1 four-layer boards, 1-4-1 six-layer boards, 2-4-2 eight-layer
boards, and 4-12-4 20-layer boards. There is discussion of using HDI in
Japanese coinage and railroad tickets as well. In other words, HDI is
being implemented rapidly in every application imaginable. If its
stronger, faster, lighter and less expensive, why not?
A major development seen at JPCA was the emergence of the EWLP
initiative, which was advertised by a number of the exhibiting interconnect
manufacturers. Billed by
CMK as the next generation in system packaging technology, EWLP is a consortium that cuts across the
component, interconnect, assembly, and OEM spectrum with the objective
of implementing and standardizing embedded active components,
specifically wafer-level packages. Participants include
CMK, Ibiden, ST Micro, Omron, Denso, Kyocera, Amkor, Sony,
Toppan, Murata and many others.
With this process, the package is mounted directly onto the innerlayer. In one process, microvias with copper posts permit the wafer
package to be connected directly to the circuits, which is said to
offer much greater interconnect reliability when compared to wire
bonding or solder. Shock and severe environment resistance are also
improved significantly by embedding active components in the board. Circuit routing distances are reduced, and heat dissipation is
reportedly also enhanced. Millions of products have shipped, including
runner’s watches, digital television tuners, and mobile handsets. EWLP
is a production reality, and is changing the identity and nature of the
interconnect, opening up new vistas for designers and OEM’s.
Several interconnect manufacturers also noted
the shorter product development cycles possible.
The nature of EWLP will change the economic structure of electronics manufacturing. Today’s industry separates
the PWB manufacturer from the assembler and, often, the OEM. The EMS industry has caused a fundamental disruption of
the economics of the finished product. Low cost rules, and those who
yank the supply chain the hardest win. EWLP requires high levels of
technology, close cooperation throughout the chain from design to
finished assembly, and higher margins at the interconnect manufacturer
based upon increased functionality and reduced overall device cost.
Those who adapt and innovate will have a bright future. Those who don’t
are doomed to play the price game.
HDI and EWLP have a direct impact on test and inspection. The stakes
are much higher as the overall value of the substrate increases. In the
case of EWLP and buried passives, the devices are already tested, and
many of them, especially 0201 resistors and capacitors, are simply the
same ones once placed by chipshooters. Test equipment
manufacturers are geared up. The fundamental test parameters
haven’t changed significantly and the electrical values remain
constant. In some ways, by freeing up real estate on the surface of the
substrate, EWLP may actually help improve testability. HDI substrates
require a high degree of precision, and impedance matching requires
more precise test parameters.
In assembly, the emphasis is on the JISSO
roadmap. The message of most major pick-and-place equipment
manufacturers was 01005 placement and 0.04 mm pitch, common scalable platforms,
and flexibility. Greater z-axis control through component height
detection and substrate warpage detection were also advertised.
Nitrogen reflow systems were widely exhibited as a yield enhancement
tool in Pb-free assembly. As elsewhere, greater system flexibility
and rapid job changeover are the reality of production in Japan. Solder
paste inspection, and chip and lead floating detection were emphasized
at the booths of the test and inspection suppliers.
Technical papers were presented on the show floor, in many cases to overflow audiences. Approximately 175 presentations were delivered on topics
ranging from semiconductor technology trends to the REACH waste
initiative. A number of these were product presentations by suppliers,
while most were less commercial. Many were related to specific
applications such as automotive and digital mobile, or processes such
as embedded components or optoelectronics. Printable circuits using ink
jet technology was another topic receiving significant attention. The three-day show was simply not long enough to delve deeper into the
possibilities of the interconnect.
As North American and European OEMs
remove themselves further from the process and technology,
they risk a loss of the means and understanding of production. With
increased functionality and higher profit margins, the interconnect is
not simply a commodity, but rather the foundation of the future.
-- by
Matt Holzmann, special to PCD&M.com.
Holzmann is president of Christopher Associates, a large distributor of PCB and assembly equipment and materials.