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Foundations for advancing wireless networks rely on the exploration of high-frequency bands ranging from 30 GHz to 300 GHz. FutureG technologies enable access to these bands with improved spectral efficiency and bandwidth. However, these trends also present significant challenges for future electronic systems. These are associated with design for higher gain and bandwidth to address higher pathlosses, interconnect losses between the transceiver and the antenna array, higher power consumption because of hardware complexity, electromagnetic interference (EMI), thermal management for higher power dissipation, limited manufacturability because of the new set of required materials, high functional density in multilayered substrates, and high production costs. Nanopackaging enables key solutions to many of these challenges by bringing advanced packaging and device materials, interfaces and package architectures to manage the complex system requirements for FutureG communications. These include nanoscale low-loss conductors, shielding structures, thermal interfaces and heat-spreaders, reconfigurable systems with tunable components, THz arrays and detectors, metasurfaces and seamless heterogeneous integration. This article reviews the key nanopackaging advances that are making FutureG communications a reality. 

Abstract Graphene has been a material of interest due to its versatile properties and wide variety of applications. However, production has been one of the most challenging aspects of graphene and multilayer graphene (MLG). Most synthesis techniques require elevated temperatures and additional steps to transfer graphene or MLG to a substrate, which compromises the integrity of the film. In this paper, metal-induced crystallization is explored to locally synthesize MLG directly on metal films, creating an MLG-metal composite and directly on insulating substrates with a moving resistive nanoheater probe at much lower temperature conditions (~ 250 °C). Raman spectroscopy shows that the resultant carbon structure has properties of MLG. The presented tip-based approach offers a much simpler MLG fabrication solution by eliminating the photolithographic and transfer steps of MLG. 

We propose a chipless RFID pH sensor which can be easily integrated into a bandage for wound monitoring. The sensor can detect the pH level from 4 to 7 of the wounded area through frequency shift owing to the pH sensitive dielectric parameter of chitosan hydrogel, embedded into the substrate of the sensor. The substrate is composed of fabric material which makes it a strong candidate for non-invasive wound monitoring application. The frequency shift can be wirelessly detected by RFID reader to get the status of the wounded area. 

Sensitive and flexible pressure sensors have invoked considerable interest for a broad range of applications in tactile sensing, physiological sensing, and flexible electronics. The barrier between high sensitivity and low fabrication cost needs to be addressed to commercialize such flexible pressure sensors. A low-cost sacrificial template-assisted method for the capacitive sensor has been reported herein, utilizing a porous Polydimethylsiloxane (PDMS) polymer and a multiwalled carbon nanotube (MWCNT) composite-based dielectric layer. The sensor shows high sensitivity of 2.42 kPa−1 along with a low limit of detection of 1.46 Pa. The high sensitivity originates from adding MWCNT to PDMS, increasing the composite polymer’s dielectric constant. Besides this, the pressure sensor shows excellent stability at a cyclic loading of 9000 cycles, proving its reliability for long-lasting application in tactile and physiological sensing. The high sensitivity of the sensor is suitable for the detection of small deformations such as pulse waveforms as well as tactile pressure sensing. In addition, the paper demonstrates a simultaneous contact and non-contact sensing capability suitable for dual sensing (pressure and proximity) with a single data readout system. The dual-mode sensing capability may open opportunities for realizing compact systems in robotics, gesture control, contactless applications, and many more. The practicality of the sensor was shown in applications such as tactile sensing, Morse code generator, proximity sensing, and pulse wave sensing. 

Wearable flexible piezo-resistive pressure sensors hold a wide-ranging potential in human health monitoring, electronic skin, robotic limbs, and other human–machine interfaces. Out of the most successful recent efforts for arterial pulse monitoring are sensors with micro-patterned conductive elastomers. However, a low-current output signal (typically in the range of nano-amperes) and bulky and expensive measurement equipment for useful signal acquisition inhibits their wearability. Herein, through a finite element analysis we establish the design rules for a highly sensitive piezo-resistive pressure sensor with an output that is high enough to be detectable by simple and inexpensive circuits and therefore ensure wearability. We also show that, out of four frequently reported micro-feature shapes in micro-patterned piezo-resistive sensors, the micro-dome and micro-pyramid yield the highest sensitivity. Furthermore, investigations of different conductivity values of micro-patterned elastomers found that coating the elastomer with a conductive material (usually metallic) leads to higher current response when compared to composited conductive elastomers. Finally, the geometric parameters and spatial configurations of micro-pyramid design of piezo-resistive sensors were optimized. The results show that an enhanced sensitivity and higher current output is achieved by the lower spatial density configuration of three micro-features per millimeter length, a smaller feature size of around 100 μm, and a 60–50 degrees pyramid angle.