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.