Implementing silicon nanoribbon field-effect transistors as arrays for multiple ion detection
journal contributionposted on 16.12.2016, 14:10 by Ralph L. Stoop, Mathias Wipf, Steffen Muller, Kristine Bedner, Iain Wright, Colin J. Martin, Edwin C. Constable, Axel Fanget, Christian Schonenberger, Michel Calame
© 2016 by the author.Ionic gradients play a crucial role in the physiology of the human body, ranging from metabolism in cells to muscle contractions or brain activities. To monitor these ions, inexpensive, label-free chemical sensing devices are needed. Field-effect transistors (FETs) based on silicon (Si) nanowires or nanoribbons (NRs) have a great potential as future biochemical sensors as they allow for the integration in microscopic devices at low production costs. Integrating NRs in dense arrays on a single chip expands the field of applications to implantable electrodes or multifunctional chemical sensing platforms. Ideally, such a platform is capable of detecting numerous species in a complex analyte. Here, we demonstrate the basis for simultaneous sodium and fluoride ion detection with a single sensor chip consisting of arrays of gold-coated SiNR FETs. A microfluidic system with individual channels allows modifying the NR surfaces with self-assembled monolayers of two types of ion receptors sensitive to sodium and fluoride ions. The functionalization procedure results in a differential setup having active fluoride- and sodium-sensitive NRs together with bare gold control NRs on the same chip. Comparing functionalized NRs with control NRs allows the compensation of non-specific contributions from changes in the background electrolyte concentration and reveals the response to the targeted species.
This work was supported by the Swiss Nano-Tera program, the European Commission under the FP7-NMP (Nanosciences, Nanotechnologies, Materials and new Production Technologies) project Hysens (263091), FP7-ICT (Information and Communication Technologies) project SYMONE (105244) and H2020 FET Open project RECORD-IT (664786) and the Swiss National Science Foundation as part of the National Centres of Competence in Research (NCCR) Molecular Systems Engineering.