Page 14 - ChipScale_May-June_2020-digital

frequencies up to the 6GHz range. For 4G
solutions, the frequency range was from
450MHZ to 3.7GHz. However, 5G mmWave
(Phase 2) will be using a frequency range
from 24GHz to 100GHz (though the
industry seems to be converging towards
an ~28GHz solution). These frequencies
are significantly higher than what are used
for the current 4G or even Phase 1 5G (at
<6GHz). Figure 11 shows the progression of
RF front-end modules from 2G and provides
a summary of packaging solutions required
for 5G sub-6GHz and 5G mmWave. In 5G
Phase 1, an extension of current packaging
solutions will work. But 5G mmWave or
Phase 2 will require new technologies, such
as phased-array antennas and antenna-
Figure 8: 2000 to 2031 global production of vehicles and the increase of electronic cost as a percent of
vehicle cost [3-5]. in-package (AiP). Because of the shorter
wavelength of 5G mmWave technology,
array (LGA) will also continue it has large losses at interconnects. The
to grow, especially using flip- antenna, therefore, will need to be designed
chip interconnect technology. in the IC chip, or at least integrated with
System in package (SIP) is the RF front-end module. Testing them cost
expected to grow significantly effectively will be even more challenging.
because of the need for New material development will be key to
heterogeneous integration produce a suitable and low-cost packaging
driven in turn by the need for solution for high-frequency devices. While
increased functionality within over-molded plastic packaging is the
the given real estate, such as in workhorse of the industry and has the largest
mobile phone applications. capacity and infrastructure in the industry,
Packaging and testing for this will not be suitable for 5G mmWave RF
5G mmWave devices will devices. For example, the mold compound
require innovative thinking used for plastic packages has a relatively
and perhaps even disruptive high dielectric constant and is not suitable
tech nolog y in novation. for RF devices above 20GHz. So, unless
Figure 9: The convergence of key technologies, along with the Historically, most IC packaging
significant unit price reduction of these fundamental technologies, will the material supplier comes up with such a
drive market growth in this decade. and testing had to deal with mold compound, a more expensive cavity
package solution will have to be used.
Finally, there remains a lack of expertise
in the assembly and test sector to effectively
handle the high-frequency RF solutions
discussed above. The semiconductor
back-end industry would need to enlist
RF engineers who understand these high-
frequency requirements and can fill this
knowledge gap for package design and
final test.
The technology convergence because of
the 5G technology revolution, improvement
in artificial intelligence, virtual and
augmented reality, and cloud computing,
along with unit cost reduction of these key
technologies will create a perfect storm that
will provide the strong backwind for the
next growth phase of the semiconductor
Figure 10: Driven by key technology convergence and lower unit cost of these technologies, the
semiconductor industry is likely to experience double-digit growth in the second half of this decade. SOURCES: industry. While 5G Phase 1 is available in
89/94 through 14/19 data from IC Insights; 15/20F through 25/30F by Asif Chowdhury a few locations and imminent in the rest of

12 Chip Scale Review May • June • 2020 [ChipScaleReview.com]
12