Chemiresistive Sensor Based on One-Dimensional WO3Nanostructures as Non-Invasive Disease Monitors

In this study, a chemiresistive sensor based on one-dimensional WO 3 nanostructures is presented for application in non-invasive med-ical diagnostics. WO 3 nanostructures were used as an active gas sensing layer and were deposited onto a SiO 2 /Si substrate using Pt inter-digitated electrodes (IDEs). The IDE spacing was 5µm and deposition was performed using RF sputter with glancing angle depositionmode. Pt IDEs fabricated by photolithography and dry etching. In comparison with thin film sensor, sensing performance of nano-structure sensor showed an enhanced response of more than 20 times when exposed to 50 ppm acetone at 400°C. Such a remarkablefaster response can pave the way for a new generation of exhaled breath analyzers based on chemiresistive sensors which are les s expen-sive, more reliable, and less complicated to be manufactured. Moreover, presented sensor technology has the potential of being usedas a personalized medical diagnostics tool in the near future. Keywords: Metal oxide gas sensors, Chemiresistive sensor, Exhaled breath analyzer, One-dimensional WO