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posed by putting more electronic content
into smaller spaces and supporting the
development of flexible electronics, including
large-area displays. Recent developments in
silicone technology can address these and
other packaging challenges, and advanced
silicones can complement rather than replace
epoxies by providing an effective wafer-level
solution.

Biography
Jayden Cho is Global Segment Leader at
Dow, Korea. His career spans 18 years in
silicones for electronics, acrylic industrial
tapes (PSAs) for electronics, and silicones
for the building industry. He holds a
Bachelor’s degree in Polymer Science
Engineering from Dankook U., Korea.
Figure 2: Silicone hybrid options for adhesives, molding and underfill. Email kcho2@dow.com
Roderick Chen is Electronics TS&D
substrate size limitations. Although SHC is not flowable at room Specialist at Dow, Taiwan. His career spans over 13 years
temperature, heating the material to 100°C supports dispensing working in the chemicals industry for semiconductor packaging
for instant bonding and sealing without bleeding. Slit die coating applications. He is skilled in materials science, electroplating,
also provides encapsulation across larger surfaces but bonds by soldering technology and silicones.
lamination instead. Compression molding, the third SHC processing
method, encapsulates chips and wafers and is recommended for flat
surfaces with a uniform thickness.
Silicone hot-melt tablets (SHT), an advanced silicone alternative
to SHF and SHC, are comparable to epoxy molding compounds
(EMC) in terms of flowability, moldability, and mechanical
strength. SHTs are processed through transfer molding and used in
applications such as IoT power modules. Advanced SHT applications
include other types of modules that operate at temperatures above
200°C. Silicone hot-melt tablets have a constant CTE up to 250°C
and exhibit thermal stability up to this same temperature. Like
other advanced silicones, they provide better thermal stability and
durability than epoxies.
Through recent developments, novel silicone hybrids are
enabling chip designers to choose adhesives, molding and
underfill materials with a distinctive balance of properties
(Figure 2). These innovative materials have a higher modulus than
silicones, but with better temperature-related performance than
epoxies. Moreover, these new packaging materials are tunable based
on application requirements and are available in non-yellowing
formulations for displays and optical modules. They cure with
ultraviolet (UV) irradiation, heat curing or dual curing that uses
both UV lights and thermal ovens.

Summary
Semiconductor manufacturers need packaging materials with
better processability, higher-temperature resistance, and improved
stress management. They also want to control production costs,
promote product reliability and reduce energy consumption, but not
at the expense of meeting requirements such as using encapsulants
that are very thin and that have a uniform thickness. As chips
become thinner, chip designers must also consider challenges

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