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Expected to become mainstream in the electronic industry, flexible electronics still face major challenging issues. For polymeric based flexible electronic substrates in particular, these challenges include a lack of electromagnetic shielding capability and poor heat dissipation. Here, we report a highly flexible and thermally-conductive macroscopic polydimethylsiloxane (PDMS) polymer film embedded with copper-coated reduced graphene oxide (rGO) fiber meshes. rGO fibers are assembled into 3D fiber meshes and electroplated with micrometer-thick copper coatings, displaying excellent electrical and thermal conductivities. Oriented in the horizontal and perpendicular directions within the PDMS polymeric matrix, the fiber mesh severs as a highly electrically and thermally-conductive backbone through the in-plane direction. Meanwhile, the fiber mesh also effectively shields electromagnetic interference in the X-band without causing thermal damage. The macroscopic film maintains electrically-insulated in the through-plane direction. Utilizing both the favorable thermal and electrical properties of the graphene fiber-based mesh and the flexibility of the PDMS matrix, our film may exhibit potentials for flexible electronics applications such as wearable electronics thermal management and flexible microwave identification devices.
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This content will become publicly available on May 1, 2026
Investigation of Graphene Film as Ground Plane Material for RF and Microwave Electronics
This study investigates the integration of reduced graphene oxide (rGO) films as ground plane in miniaturized RF/mm-wave systems for advanced thermal management applications. Traditional methods such as copper-based heat spreaders struggle to handle the increased power and tighter integration requirements of modern day RF/mmWave packaging. Due to rGO’s exceptionally high in-plane thermal conductivity (∼1100 W/mK), when compared with copper (∼400 W/mK), rGO emerges as a compelling candidate for thermal management in RF electronic packaging. This study investigates the use of rGO to form a ground plane in RF and microwave electronics, evaluating its performance through meticulous transmission line simulations and measurements. Our findings reveal that rGO ground planes exhibit high signal integrity, with an average loss of about 1 dB at 10 GHz and around 2 dB up to 26 GHz, comparable to the performance of traditional copper ground planes. These results indicate that rGO is a promising material for RF and microwave circuits, especially in applications requiring enhanced thermal management and mechanical flexibility.
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- Award ID(s):
- 2329207
- PAR ID:
- 10635803
- Publisher / Repository:
- IEEE
- Date Published:
- Journal Name:
- IEEE Transactions on Components, Packaging and Manufacturing Technology
- Volume:
- 15
- Issue:
- 5
- ISSN:
- 2156-3950
- Page Range / eLocation ID:
- 1143 to 1150
- Subject(s) / Keyword(s):
- Advanced RF materials, graphene film, reduced graphene oxide (rGO), wave–matter interaction.
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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