Incorporating molecular nanolayers (MNLs) at inorganic interfaces offers promise for reaping unusual enhancements in fracture energy, thermal and electrical transport. Here, we reveal that multilayering MNL-bonded inorganic interfaces can result in viscoelastic damping bandgaps. Molecular dynamics simulations of Au/octanedithiol MNL/Au multilayers reveal high-damping-loss frequency bands at 33 ≤ ν ≤ 77 GHz and 278 ≤ ν ≤ 833 GHz separated by a low-loss bandgap 77 ≤ ν ≤ 278 GHz region. The viscoelastic bandgap scales with the Au/MNL interface bonding strength and density, and MNL coverage. These results and the analyses of interfacial vibrations indicate that the viscoelastic bandgap is an interface effect that cannot be explained by weighted averages of bulk responses. These findings prognosticate a variety of possibilities for accessing and tuning novel dynamic mechanical responses in materials systems and devices with significant inorganic–organic interface fractions for many applications, e.g., smart composites and sensors with self-healing/-destructing mechanical responses.
This content will become publicly available on April 1, 2025
Nanopackaging for FutureG Solutions
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.
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- Award ID(s):
- 2029007
- NSF-PAR ID:
- 10509582
- Publisher / Repository:
- IEEE
- Date Published:
- Journal Name:
- IEEE Nanotechnology Magazine
- Volume:
- 18
- Issue:
- 2
- ISSN:
- 1932-4510
- Page Range / eLocation ID:
- 10 to 20
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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