We present a novel fabrication technique for large-scale, on-wafer graphene devices. With the proposed technique, large-area graphene apertures can be fabricated, enabling the proliferation of graphene-based reconfigurable devices, including metasurfaces. Such topologies require large-area high yield fabrication processes. To avoid graphene delamination during the chemical processes of the fabrication, we use a titanium sacrificial layer to protect the graphene monolayer. To evaluate the fabrication method, we present broadband in-plane graphene measurements in the 220-330 GHz band for the first time and compare the measured resistance sheet with previous works.
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On-Wafer Graphene Devices for THz Applications Using a High-Yield Fabrication Process
We characterize a novel fabrication procedure for the implementation of large arrays of subwavelength graphene devices. With the proposed process, we can now integrate graphene layers on large substrate areas (> 4 cm2) and implement thousands of devices with high-yield (> 90 %). Examples of such systems include broadband THz phased arrays and metasurfaces that can be used in THz imaging and sensing. Current nano-fabrication processes hinder the proliferation of large arrays due to the fragile nature of graphene. Conversely, we use titanium sacrificial layers to protect the delicate graphene throughout the fabrication process. Thus, we minimize graphene delamination and enable multiple devices on large-area substrates with high-yield. In addition, we present a series of on-wafer measurement results in the 220-330 GHz band, verifying the robustness of our fabrication process.
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- Award ID(s):
- 1847138
- NSF-PAR ID:
- 10135990
- Date Published:
- Journal Name:
- 2019 IEEE MTT-S International Microwave Symposium (IMS)
- Page Range / eLocation ID:
- 1107 to 1110
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/MWSYM.2019.8701093
