Batch Nanofabrication of Suspended Single 1D Nanoheaters for Ultralow‐Power Metal Oxide Semiconductor‐Based Gas Sensors

Abstract

The demand for power‐efficient micro‐and nanodevices is increasing rapidly. In this regard, electrothermal nanowire‐based heaters are promising solutions for the ultralow‐power devices required in IoT applications. Herein, a method is demonstrated for producing a 1D nanoheater by selectively coating a suspended pyrolyzed carbon nanowire backbone with a thin Au resistive heater layer and utilizing it in a portable gas sensor system. This sophisticated nanostructure is developed without complex nanofabrication and nanoscale alignment processes, owing to the suspended architecture and built‐in shadow mask. The suspended carbon nanowires, which are batch‐fabricated using carbon‐microelectromechanical systems technology, maintain their structural and functional integrity in subsequent nanopatterning processes because of their excellent mechanical robustness. The developed nanoheater is used in gas sensors via user‐designable localization of the metal oxide semiconductor nanomaterials onto the central region of the nanoheater at the desired temperature. This allows the sensing site to be uniformly heated, enabling reliable and sensitive gas detection. The 1D nanoheater embedded gas sensor can be heated immediately to 250 °C at a remarkably low power of 1.6 mW, surpassing the performance of state‐of‐the‐art microheater‐based gas sensors. The presented technology offers facile 1D nanoheater production and promising pathways for applications in various electrothermal devices.

Anchoring Pt Particles onto Mesoporousized ZnO Holey Cubes for Triethylamine Detection with Multifaceted Superiorities

“…Furthermore, these H 2 O molecules could react with the oxygen species on the surface to produce OH and H + , leading to the consumption of active oxygen species and release of electrons. [38] Selectivity is also an important aspect in gas detection applications. Thus, the selectivity of these three sensors have been evaluated towards 200 ppm of various gases, as depicted in Figure 7c,d.…”

“…Furthermore, these H 2 O molecules could react with the oxygen species on the surface to produce OH and H + , leading to the consumption of active oxygen species and release of electrons. [ 38 ]…”

Nanowatt‐Level Photoactivated Gas Sensor Based on Fully‐Integrated Visible MicroLED and Plasmonic Nanomaterials

“…The joule heating method minimized the heating area by fabricating microheaters and nanowire heaters with MEMS/ NEMS technology to reduce power consumption, but the power consumption was still high on the milli-watts scale. [4,8,42,43] Selfheating SnO 2 nanowire lowered the power consumption to µW-scale (continuous mode), but still failed to lower it to nanowatts scale, and its mechanical/thermal stability is very vulnerable due to its sensor structure in which a single nanowire is suspended. [9] Recently, photoactivated gas sensors integrated with various light activation sources such as optical fibers, mini LEDs, and micro LEDs have been introduced.…”

Ultrathin Serpentine Insulation Layer Architecture for Ultralow Power Gas Sensor

“…Additionally, the structural distancing of the heating and sensing nanowires established electrical isolation even with an ultrathin insulation thickness. As a result, the proposed gas sensor consumed only 2.3 mW with an operating temperature of 300 °C, showing superior heating efficiency when compared with those of other works [31,40,[42][43][44][45][46][47][48] and commercial products (≈6% of the leading commercial product). [49] Furthermore, our proposed gas sensor was able to endure harsh electrical measurements, showing negligible optical and electrical degradation even after being subjected to temperature elevations of up to 600 °C and enduring 10 000 cycles of operation at a working temperature of 300 °C.…”