@misc{10481/85137,
year = {2023},
month = {9},
url = {https://hdl.handle.net/10481/85137},
abstract = {Even though a plethora of printing technologies are currently available and their potential for the
fabrication of low-cost and flexible sensors has been widely investigated, systematically based, and
statistically sustained comparative studies are missing in the literature. In this work, we compare
screen, inkjet, and dispense printing for the fabrication of carbon nanotube (CNT)-based
ammonia (NH3) chemiresistive flexible gas sensors for the first time. Moreover, we report the first
CNT-based gas sensor fabricated via Voltera printer. The devices were made of a thin layer of
spray-coated CNTs and printed silver-based interdigitated electrodes. To draw a thoughtful
comparison the same sensor layout, materials, and fabrication flow were used. The device
morphological features were acquired through microscopic, atomic force microscope, and 3D
images; additionally, the response to NH3 as well as the printing process characteristics for each
technique was analyzed. From 300 μm nominal spacing between lines, we obtained a decrease of
25%, 13%, and 5% on the printed spacings with dispense, screen, and inkjet printing, respectively.
At 100 ppm of NH3, a maximum response of 33%, 31%, and 27% with the dispense-, inkjet-, and
screen-printed sensors were found, respectively. Statistical differences were observed between the
mean values on the NH3 response of dispense- compared to the inkjet- and screen-printed sensors,
which in effect showed the highest response in the Tukey test. This demonstrated that the
fabrication technique employed can induce a different response mainly driven by the printed
outcomes. Following a holistic approach that includes the sensor response, the application, the
market perspective, and the process versatility, we suggest screen printing as the most suitable
method for CNT-based NH3 gas sensor fabrication.
1. Introduction
In the last decade, several manufacturing technologies
have been extensively exploited to fabricate
gas sensors, including chemical vapor deposition [1],
physical vapor deposition [2], micromachining [3],
self-assembly [4], spray coating [5, 6], and printing
[7, 8]. Among all, the latter is the most commonly
utilized technology for developing miniaturized,
portable, and low-cost sensors [9]. Indeed, over
the},
organization = {European Regional Development Fund (ERDF)
Program (Project codes EFRE/FESR 1068-Senslab
and EFRE/FESR 1127-STEX)},
organization = {Free University of
Bozen-Bolzano},
publisher = {IOPScience},
keywords = {Dispense printing},
keywords = {Screen printing},
keywords = {Inkjet printing},
keywords = {Carbon nanotubes},
keywords = {Chemiresistive sensors},
keywords = {Ammonia},
title = {Comparison of printing techniques for the fabrication of flexible carbon nanotube-based ammonia chemiresistive gas sensors},
doi = {10.1088/2058-8585/acef39},
author = {Vasquez, Sahira and Rivadeneyra Torres, Almudena},
}