A Linear-Array of 300-GHz Antenna Integrated GFET Detectors on a Flexible Substrate

Abstract

Terahertz imaging has potential in a variety of applications, such as noninvasive inspection, medical examination, and security. Many of these applications call for flexible focal-plane arrays with large fields of view. Here, we demonstrate the implementation of a flexible, 300 GHz, 1\times 6 linear detector array based on graphene field-effect transistors and integrated bow-tie antennas. Conservative estimates based on room temperature measurements at 300 GHz show element voltage responsivities in the range from 20 to 70 V/W, and noise equivalent powers in the range from 0.06 to 0.2 nW/\sqrt{\mathrm{Hz}}. Measured radiation patterns, showing good agreement with simulations, reveal half-power beamwidths of 45^\circ and 60^\circ for H- and E-planes, respectively. Characterization of the antenna array in a curved configuration shows that the voltage response is reduced up to 3 dB compared to the flat configuration due to a decrease of the antenna directivity. We believe that our preliminary results could serve as an enabling platform for the future development of flexible antenna arrays based on graphene field-effect transistors for curved focal plane imaging, important for wearable sensors and many other applications.