Report from the IEEE/CPMT Session held at
the NEPCON West 99
NEPCON West 99 Conference and Exhibition took place in
its standard location in Anaheim, California, February 22-25,
1999. This event is most known for its very large and well-attended
exhibition that fills all the halls of the Anaheim Convention
Center. Less known is the accompanying Technical Program that
is held at the Marriott Hotel. The 3-day conference had 42 sessions,
with 7 sessions running in parallel any given morning and afternoon.
Best attendance for the conference is found on Monday, before
the exhibits open,
after which the Conference also competes with the giant Expo with
close to 1,000 exhibitors.
This year, IEEE CPMT Society agreed to sponsor one of the technical
sessions. The initial idea was that the session would feature
some of the papers given at last years ECTC Conference in
San Jose. As such, the papers would not have been submitted in
the Conference Proceedings (a hefty 3-volume set, which can also
be had as a CD-ROM). However, as the recruiting process for those
speakers got under way, it was realized that the presentations
would not be duplicates of the ECTC Conference and that additional
speakers would be presenting, so ultimately the session and its
papers did get into the Conference Proceedings.
The IEEE/CPMT Session (Session no. 41) was held on Wednesday,
February 24 at 1PM and was titled "Materials and Reliability
Issues in New Plastic Packages," reflecting the nature of
the papers presented. The session had a full program of 6 speakers;
number of speakers in other sessions varied from 4 to 6. The
first three presentations related to package reliability issues,
while the last three covered materials used in packages and their
reliability issues.
The first paper was given by Dr. Reza Gaffarian, who heads
up the JPL Quality Assurance Office effort in determining the
reliability of new BGA and CSP packages. He presented some of
the failure mechanisms seen in the testing of these packages and
discussed the various issues in their assembly. Rick
Sigliano of Kyocera presented the development of new plastic packages
that are designed to replace the traditional ceramic packages.
The approach uses a novel set of materials which are based on
ceramic polymer composites and can tailor the desired dielectric
constant. The third paper was given by Dr. John Xie of ProLinx
and it described the reliability testing of a novel BGA package
that uses a metal core. The additively processed circuitry uses
photoimageable dielectrics providing for filled vias and high-density
circuitry on a high thermal dissipation copper substrate.
Michael Todd of Dexter Electronic Materials gave a presentation
on the effects of moisture on underfill mechanical properties.
The role of the intrinsic material properties as well as the
interface adhesion on the reliability properties related to moisture
exposure was presented. The use of Newtonian
Molecular Modeling and Discrete Modeling Techniques in predicting
material trends was presented by Dr. Nancy Iwamoto of Johnson
Matthey. This work, done in collaboration with the Colorado School
of Mines is seeking to extend the use some of the latest techniques
that have recently gained popularity in the
pharmaceutical industry to the field of electronic polymers and
use to use them in determining material parameters such as flow
and surface properties.
Dr. Jack Zhang of Dexter Electronic Materials (QMI) presented
a theoretical as well as experimental analysis on the effect of
material properties of die attach adhesives on stress in molded
plastic packages. The presentation discussed the effects of cure
shrinkage and moisture on the stresses that are generated in the
packages. The presentations raised several questions from
the audience on the issues raised.
Latest information on the NEPCON set of conferences is that
the conference organizers have partnered up with SMTA (Surface
Mount Technology Association) and that SMTA will help in the organization
of future NEPCON Technical sessions. Meanwhile, IPC has announced
that a new Electronics Assembly
Process Exhibition and Conference will debut next year, organized
by its Surface Mount Equipment Manufacturers Association
(SMEMA).
--Dr. Goran Matijasevic, IEEE/CMPT Session Chair