TY - JOUR
T1 - Long-Term Stability of Oxide Nanowire Sensors via Heavily Doped Oxide Contact
AU - Zeng, Hao
AU - Takahashi, Tsunaki
AU - Kanai, Masaki
AU - Zhang, Guozhu
AU - He, Yong
AU - Nagashima, Kazuki
AU - Yanagida, Takeshi
N1 - Funding Information:
This work was supported by CREST of Japan Science and Technology Corporation (JST). Y. T. was supported by ImPACT. H. Z., T. T., Z. G., Y. H., and K. N were supported by KAKENHI Grant Numbers (No.17H04927, No.26706005, No.16H00969, No.15K13288, No.15H03528, No.26220908). This work was performed under the Cooperative Research Program of “Network Joint Research Center for Materials and Devices” and the MEXT Project of “Integrated Research Consortium on Chemical Sciences”.
Publisher Copyright:
© 2017 American Chemical Society.
PY - 2017/12/22
Y1 - 2017/12/22
N2 - Long-term stability of a chemical sensor is an essential quality for long-term collection of data related to exhaled breath, environmental air, and other sources in the Internet of things (IoT) era. Although an oxide nanowire sensor has shown great potential as a chemical sensor, the long-term stability of sensitivity has not been realized yet due to electrical degradation under harsh sensing conditions. Here, we report a rational concept to accomplish long-term electrical stability of metal oxide nanowire sensors via introduction of a heavily doped metal oxide contact layer. Antimony-doped SnO2 (ATO) contacts on SnO2 nanowires show much more stable and lower electrical contact resistance than conventional Ti contacts for high temperature (200 °C) conditions, which are required to operate chemical sensors. The stable and low contact resistance of ATO was confirmed for at least 1960 h under 200 °C in open air. This heavily doped oxide contact enables us to realize the long-term stability of SnO2 nanowire sensors while maintaining the sensitivity for both NO2 gas and light (photo) detections. The applicability of our method is confirmed for sensors on a flexible polyethylene naphthalate (PEN) substrate. Since the proposed fundamental concept can be applied to various oxide nanostructures, it will give a foundation for designing long-term stable oxide nanomaterial-based IoT sensors.
AB - Long-term stability of a chemical sensor is an essential quality for long-term collection of data related to exhaled breath, environmental air, and other sources in the Internet of things (IoT) era. Although an oxide nanowire sensor has shown great potential as a chemical sensor, the long-term stability of sensitivity has not been realized yet due to electrical degradation under harsh sensing conditions. Here, we report a rational concept to accomplish long-term electrical stability of metal oxide nanowire sensors via introduction of a heavily doped metal oxide contact layer. Antimony-doped SnO2 (ATO) contacts on SnO2 nanowires show much more stable and lower electrical contact resistance than conventional Ti contacts for high temperature (200 °C) conditions, which are required to operate chemical sensors. The stable and low contact resistance of ATO was confirmed for at least 1960 h under 200 °C in open air. This heavily doped oxide contact enables us to realize the long-term stability of SnO2 nanowire sensors while maintaining the sensitivity for both NO2 gas and light (photo) detections. The applicability of our method is confirmed for sensors on a flexible polyethylene naphthalate (PEN) substrate. Since the proposed fundamental concept can be applied to various oxide nanostructures, it will give a foundation for designing long-term stable oxide nanomaterial-based IoT sensors.
UR - http://www.scopus.com/inward/record.url?scp=85039156855&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85039156855&partnerID=8YFLogxK
U2 - 10.1021/acssensors.7b00716
DO - 10.1021/acssensors.7b00716
M3 - Article
C2 - 29057648
AN - SCOPUS:85039156855
SN - 2379-3694
VL - 2
SP - 1854
EP - 1859
JO - ACS sensors
JF - ACS sensors
IS - 12
ER -