Page 6 - ChipScale_Jan-Feb_2020-digital

TECHNOLOGY TRENDS

Antenna in package (AiP): disrupting

wireless communication and HMI

By Stéphane Elisabeth [System Plus Consulting], Cédric Malaquin [Yole Développement], both part of the
Yole Group of Companies
A ny wireless system requires

antennas to convert the
electric energy into radio
waves traveling through
the air. Whether it is for wireless sensing
or broadband communication between at
least two points, multiple types of antennas
have been developed depending on the
targeted application. Monopole, dipole,
yagi, dish, patch, etc., are some of the
existing configurations. Recently, a new
type of system configuration, called antenna
in package (AiP), has appeared and is
becoming more and more popular, at least in Figure 1: State of the art of the 4G and Sub-6 RF Layout; Qorvo QM76018 (left) [1] and Broadcom (AFEM-8092)
the consumer market. In this article we will (right) [2]. SOURCES: [1,2]
review the market drivers and the state of the
art, as well as the market potential for AiP. two different frequency domains (mid band 6GHz frequencies, that means an antenna
and high band) are utilized in this device, tuner is increasingly becoming a key
Advanced packaging: innovation for complex electromagnetic interference component. At millimeter wave frequencies,
(EMI) shielding techniques have been
however, AiP and antenna-on-package
consumer connectivity apps employed to isolate the different bands. In (AoP) comes into play. At millimeter-wave
In the consumer market, the main Qorvo’s module, EMI shielding is using the frequencies, antenna size reaches the RF
technology deployed for cellular and Wi- package laminate substrate with a ground integrated circuit’s (RFIC) form factor. In
Fi connectivity is based on relatively trace, whereas Broadcom uses grounded addition, RF losses are such that integrating
low frequencies, the so-called sub- palladium-coated copper (PPC) wire bonded the antenna along with the RFIC is no
6GHz frequency range. Because of the onto critical components to be protected. As longer an option, it is now mandatory.
sparse and poor spectrum holding from RF component integration density is still
network providers, complex technologies increasing, the latest RF system-in-package
such as carrier aggregation and multiple- (SiP) modules found in the Apple iPhone 5G mmWave has democratized AiP
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input multiple-output (MIMO) have been 11 now come in double-sided ball grid array technology
deployed to comply with the never-ending (BGA) packaging with EMI shielding [3]. AiP is a relatively new concept that
increasing demand for data consumption. For low-end smartphones, where cost is has already made its way to the market.
In the meantime, RF board allocation has more important than the form factor, the The most notable example is Samsung’s
shrunk in the mobile handset because of mainstream packaging is SiP using long flagship phone, the S10 5G commercialized
restricted space with a larger battery size grid array (LGA) [4,5]. in the US market for Verizon’s 5G ultra-
and new features added. This strategy has In fact, the iPhone 11 still is an advanced wideband (UWB) subscribers. The device
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put pressure on RF front-end module makers LTE phone. With the 5G roll out, the currently supports 26, 28 and 39GHz
and outsourced semiconductor assembly densification trend of RF components in a bands thanks to the combination of a
and test (OSAT) companies to develop mobile handset will extend to sub-6GHz baseband processor (X50M) along with
very complex packaging technologies. An frequencies. But the story is different for three AiP modules (QTM052) integrated
example of dense RF component integration 5G mmWave applications. In the sub-6GHz into the phone case. Two generations of
is shown in Figure 1. world, antenna integration is not possible AiP have been used for this phone [6]. The
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The Apple iPhone Xr features one or on account of the size and location of the first one, as shown in Figure 2, features a
another module for dual-sourcing reasons antenna. Instead, antennas are connected PMIC, several passive components, and a
(shown in Figure 1). Both modules are pin- to the modules with a coaxial cable, printed transceiver on the bottom side of the PCB.
to-pin compatible and include all necessary circuit board (PCB) or flex PCB. A basic The transceiver is connected to two types
RF components: acoustic wave filters requirement for the consumer market is that, of antennas through the package laminate
(in red), RF switches (in green), a power whenever possible, antenna size needs to be substrate. The first type of antenna consists
amplifier (in purple), a low-noise amplifier shrunk down to comply with the stringent of eight dipoles embedded in the layer of
(in yellow) and a power management system integrator requirements. For sub- the laminate substrate and isolated from the
integrated circuit (PMIC) (in blue). Because transceiver by a compartment shielding.

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