Publication detail

On-chip sensor solution for hydrogen gas detection with the anodic niobium-oxide nanorod arrays

PYTLÍČEK, Z. BENDOVÁ, M. PRÁŠEK, J. MOZALEV, A.

Original Title

On-chip sensor solution for hydrogen gas detection with the anodic niobium-oxide nanorod arrays

Type

journal article in Web of Science

Language

English

Original Abstract

Two types of anodic niobium-oxide nanofilms were synthesized via anodization of an Al/Nb bilayer sputterdeposited onto a SiO2-coated Si wafer. Type I nanofilm was composed of a 200 nm thick NbO2 layer holding the upright-standing 650 nm long, 50 nm wide, and 70 nm spaced Nb2O5 nanorods, of 7·109 cm−2 density, whereas the Type II nanofilm had similarly long but bigger Nb2O5 nanorods, 100 nm wide, 220 nm spaced, and of 8·108 cm−2 density, aligned directly on a niobium metal without any buffering oxide layer, which was achieved for the first time. Each film was then incorporated in an advanced 3-D architecture and multilayer layout on a silicon chip comprising 33 microsensors, with variable sizes and tuned electrical characteristics, by combining the high-temperature vacuum or air annealing, sputter-deposition and lift-off photolithography to form Pt/NiCr top electrodes and a multifunctional SiO2 interlayer, chemical etching, laser dicing, and ultrasonic wire-bonding. The proposed on-chip sensor solution allowed for a sensitive, fast, and highly selective (toward NH3 and CH4) detection of hydrogen gas. Comprehensive gas sensing tests performed for Type II nanofilm ultimately confirmed the presence of a Schottky-type sensing mechanism, the contribution, however, being substantially weaker than that due to reactions over the surface of the oxide nanorods, especially when the rods show a transition from fully to partially depleted states when interacting with H2 gas. The film formation and chip fabrication technologies may be transferable to other PAA-assisted 1-dimensional metal-oxide nanomaterials suitable for on-chip gas sensing.

Keywords

On-chip sensor; Anodizing; Anodic alumina; Niobium oxide nanorods; Hydrogen; Schottky barrier

Authors

PYTLÍČEK, Z.; BENDOVÁ, M.; PRÁŠEK, J.; MOZALEV, A.

Released

1. 4. 2019

Publisher

Elsevier B.V.

ISBN

0925-4005

Periodical

Sensors and Actuators B: Chemical

Year of study

284

Number

1

State

Swiss Confederation

Pages from

723

Pages to

735

Pages count

13

URL

https://www.sciencedirect.com/science/article/pii/S0925400519300280

BibTex

@article{BUT152153,
  author="Zdeněk {Pytlíček} and Mária {Bendová} and Jan {Prášek} and Alexander {Mozalev}",
  title="On-chip sensor solution for hydrogen gas detection with the anodic niobium-oxide nanorod arrays",
  journal="Sensors and Actuators B: Chemical",
  year="2019",
  volume="284",
  number="1",
  pages="723--735",
  doi="10.1016/j.snb.2019.01.009",
  issn="0925-4005",
  url="https://www.sciencedirect.com/science/article/pii/S0925400519300280"
}