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A growing interest in AI and deep learning applications necessitates the development of efficient power delivery networks (PDNs) to manage broadband impedance in high-speed switching environments. This paper evaluates the electromagnetic performance of horizontal, vertical, and embedded PDNs in fanout packages, with particular emphasis on vertical and embedded configurations, both less explored for noise mitigation. Simulations indicate that embedded PDNs significantly reduce commonmode (CM) and differential-mode (DM) radiation, achieving levels between 20-78 dBµV. Additionally, measurements show that embedded PDNs maintain a lower electric field strength of 1.9 V/m for DM radiation as compared to 2.7 V/m for horizontal PDNs and 11.4 V/m for vertical PDNs. Advanced shielding with 5-µm thick Cu-CoNiFe layers further reduces magnetic field emissions by 30-45 dB. These findings demonstrate that embedded PDNs are a more effective solution for electromagnetic interference (EMI) mitigation in future electronic systems, offering superior noise control and reduced crosstalk. 

Electromagnetic shielding often requires the integration of thick shielding structures in the form of metal casings, walls, or via arrays. These shields typically isolate the entire package from external or internal noise sources. In some cases, they also isolate components within the package. However, integration of shielding structures with the required performance creates miniaturization and fabrication constraints, and results in longer product development cycle times. To address these limitations, a novel approach is presented for component- and package-level shielding. This approach is based on electromagnetic interference (EMI) shield integration through a microassembly of prefabricated shields inside microslots in packages and printed circuit boards (PCBs). This approach eliminates many of the design and process constraints during the shield integration within packages. Various design options were considered to mitigate capacitive and inductive coupling between representative microstrip lines that act as aggressors and victims. Three types of EMI shielding architectures, U-shaped, inverted-L-shaped, and T-shaped, were investigated with 17.5 μm copper. The fabricated EMI shields were studied for their shield performance, both as a compartmental shield between specific components and as a conformal shield from external and internal noises. The role of the ground termination was also investigated to further optimize the shielding performance. 

Electromagnetic compatibility (EMC) is a key requirement for electronic system design. Meeting the EMC regulations becomes more challenging as the component density increases and operation frequencies spread to multiple bands. Coupling between transmission lines is a common manifestation of electromagnetic interference (EMI). In this work, we present a novel method to suppress the noise between two transmission lines by using a metamaterial (MTM) structure. This MTM design helps to mitigate the coupling between the two transmission lines where one acts as an aggressor and the other as the victim. This approach helps miniaturize the solutions such as shielding or filtering to mitigate the noise. MTM provides good protection in terms of EMI isolation, is inexpensive, and has a smaller footprint compared to traditional EMC solutions. The second part of this article studies the impact of the relative permittivity (ε r ) of the MTM structure. Changing the ε r modifies the transmission and absorption bands. Thus, that can help in modulating the operation of the MTM through appropriate designs. The MTM designs used in this work enhanced the isolation between the victim and aggressor by 1–13.5 dB across 1–5 GHz. 

Reconfigurable Intelligent Surfaces (RIS) also known as Intelligent Reflecting Surfaces (IRS) often depend upon metasurfaces. These typically comprise of a large array of passive elements that can be fabricated to modulate reflection amplitude or phase or both to create tunable functions that are independently controlled. Various RIS are developed to improve spectral efficiency through ultrawideband antennas, enhanced beamforming with higher gain and bandwidth, spatial reconfigurability, selective and adjustable isolation, and other desired features. Several approaches to tune the RIS performance are being explored. This paper reviews the primary approaches and the benefit of emerging tunable nanomaterials in achieving such RIS functions. Designs with 1-bit and 6-bit phase shifters are discussed in the first part. Various opportunities with nanomaterials and nanodevices to induce such phase shifts are discussed in the last part of the paper.