A hybrid YSZ/SnO₂/MEMS SO₂ gas sensor

Abstract

This study uses a solid YSZ electrolyte film in a SnO2 MEMS SO2 gas sensor of the semiconductor type to enhance the redox reaction.

Sensitive and Low-Power Metal Oxide Gas Sensors with a Low-Cost Microelectromechanical Heater

“…The remaining two steps aim to pattern an isolation layer between the microheater and the sensing film, and to make a mask to expose the silicon for wet etching, respectively. 32 In general, more process steps usually lead to longer development time, lower yield and ultimately higher cost. Hence, to facilitate the high-volume adoption of MEMS-type gas sensors, a strategy to further simplify the fabrication process is highly desired.…”

“…Specifically, the fabrication usually involves four sequential lithography steps: (a) Mask one creates a layer of a patterned serpentine metal resistor for ohmic heating, (b) mask two produces a patterned SiN x insulating layer where the bonding pads are exposed, (c) mask three defines the sensing electrode, and (d) mask four forms selective openings on the insulating membrane for the subsequent anisotropic wet etching. More recently, some researchers use a single photolithography step to define both the microheater and IDE structure on the suspension platform, where IDEs are enclosed by the serpentine microheater to minimize unwanted thermal diffusion. , Therefore, the fabrication process can be reduced to three lithography steps. The remaining two steps aim to pattern an isolation layer between the microheater and the sensing film, and to make a mask to expose the silicon for wet etching, respectively .…”

“…More recently, some researchers use a single photolithography step to define both the microheater and IDE structure on the suspension platform, where IDEs are enclosed by the serpentine microheater to minimize unwanted thermal diffusion. , Therefore, the fabrication process can be reduced to three lithography steps. The remaining two steps aim to pattern an isolation layer between the microheater and the sensing film, and to make a mask to expose the silicon for wet etching, respectively . In general, more process steps usually lead to longer development time, lower yield and ultimately higher cost.…”

Fabrication of ZnO/CNTs for Application in CO2 Sensor at Room Temperature

“…This is due to the advantages of MOS gas sensors, which include low power consumption, low cost, high sensitivity, and quick response, with excellent microelectronic processing compatibility [12]. To improve the CO 2 sensor, several semiconductor materials, such as tin dioxide (SnO 2 ), tungsten trioxide (WO 3 ), copper oxide (CuO), and zinc oxide (ZnO), were used [13][14][15]. ZnO is an n-type semiconductor with a wide optical bandgap energy (3.37 eV).…”

Sensing Properties of Vacancy and Pd-Doped Graphene Layer: A First-Principles Study

“…To control environmental acidification and ensure better GIS insulation, detecting residual SO2 gases has become a priority for environmental surveillance. In recent years, numerous types of gas sensors have been designed for this purpose to accurately monitor SO2 concentration levels and lay the foundation for environmental governance [6][7][8][9][10].…”