Laser-Induced Periodic Surface Structures and Their Application for Gas Sensing

Area of Science:

• Materials Science
• Nanotechnology
• Sensor Technology

Background:

• Semiconducting metal oxides are crucial for various applications, including gas sensors.
• Device performance in gas sensors is significantly influenced by surface topology.
• Increasing the sensing area is key to improving sensor efficiency.

Purpose of the Study:

• To explore methods for enhancing the sensing area of semiconducting metal oxide gas sensors.
• To investigate the fabrication and characterization of micro- and nanopatterned surfaces.
• To evaluate the performance of nanostructured sensors for gas detection.

Main Methods:

• Generation of laser-induced periodic surface structures (LIPSSs) on silicon, Si/SiO2, and glass substrates.
• Fabrication of nanostructured Ni/Au and Ti/Au films on glass via laser ablation.
• Surface morphology examination using Field Emission Scanning Electron Microscopy (FE SEM).
• Hydrogen sensitivity testing using transmittance measurements.

Main Results:

• Nanostructuring glass substrates using backside ablation yielded 100 nm features with high surface area, transparency, and high resistivity.
• Nanostructured TiO2/Au demonstrated twice the hydrogen sensitivity compared to NiO/Au for concentrations between 100-500 ppm.
• Transparent nanostructured materials show potential for optical gas sensing.

Conclusions:

• Laser ablation is a suitable method for creating nanostructured surfaces that enhance gas sensor performance.
• The developed transparent nanostructured materials offer a pathway for novel optical gas sensors.
• Optimized surface topology significantly boosts the sensitivity of semiconducting metal oxide gas sensors.