Photosensitive Field-Effect Transistors Made from Semiconducting Carbon Nanotubes and Non-Covalently Attached Gold Nanoparticles

The authors propose an on-chip microfluidic flow chemistry for non-covalent functionalization of single-walled carbon nanotubes (SWCNTs) as channel material in nanoelectronic carbon-nanotube field-effect transistors (CNT-FETs) specifically aiming for personalized optoplasmonic sensor solutions. Applying pyrene alkanethiol derivatives, dissolved in chloroform, and a dispersion of gold nanoparticles in triglyme, the authors conduct the proof-of-principle to fabricate arrays of photosensitive CNT-FETs using flow chemistry on wafer-compatible hardware. The spectral photoresponse of the obtained sensor devices appears clear and reproducible and can be related to the surface plasmon polaritons of the gold nanoparticles. The sensor devices yield photometric responsivities of RA ≈ 8 × 10−3 AW−1 and response times of t0 ≈ 9 s. The results extend a previously reported approach for covalent functionalization (Blaudeck et al., Microelectron. Eng. 2015, 137, 135) and show the potential of flow chemistry combined with wafer-level microfabrication for selectively functionalized nanostructured sensor arrays.