On-Chip Glucose Sensing at Terahertz Frequencies

Mohsen Haghighat; Thomas Darcie; Levi Smith

doi:10.1038/s41598-024-81731-1

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arXiv · 2406.07701

On-Chip Glucose Sensing at Terahertz Frequencies

Mohsen Haghighat·Thomas Darcie·Levi Smith

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Abstract

This paper demonstrates an on-chip anhydrous D-glucose sensor based using a coplanar stripline (CPS) on a thin (1 um) silicon nitride membrane at terahertz (THz) frequencies. A thin layer (~10 um) of D-glucose was placed in close proximity to the CPS and the transmission response was measured using a modified THz-TDS setup. The D-glucose introduces frequency-dependent changes to the effective permittivity of the CPS resulting in a modified spectral response at the receiver. Measurement results show absorption signatures at 1.42 THz and 2.07 THz corresponding to the first two significant resonances beyond 1 THz for D-glucose allowing for label-free detection. The frequency-dependent attenuation coefficient was estimated by simulation for several D-glucose layer thicknesses using a modified Lorentz model. Measurement results align with simulations and other literature that use free-space THz radiation. This work verifies on-chip THz sensing of D-glucose and presents a pathway towards on-chip sensing of other materials at THz frequencies.

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Mohsen Haghighat, Thomas Darcie, Levi Smith. 2024-06-11. On-Chip Glucose Sensing at Terahertz Frequencies. https://doi.org/10.1038/s41598-024-81731-1

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