As highly sensitive H2S gas sensors, Au- and Ag-catalyzed SnO<inf>2</inf> thin films with morphology-controlled nanostructures were fabricated by using e-beam evaporation in combination with the glancing angle deposition (GAD) technique. After annealing at 500 °C for 40 h, the sensors showed a polycrystalline phase with a porous, tilted columnar nanostructure. The gas sensitivities (S = R<inf>gas</inf>/R<inf>air</inf>) of Au and Ag-catalyzed SnO<inf>2</inf> sensors fabricated by the GAD process were 0.009 and 0.015, respectively, under 5 ppm H<inf>2</inf>S at 300 °C, and the 90% response time was approximately 5 s. These sensors showed excellent sensitivities compared with the SnO<inf>2</inf> thin film sensors that were deposited normally (glancing angle = 0°, S = 0.48).
- Glancing angle deposition
- H<inf>2</inf>S sensor
- SnO<inf>2</inf> nanocolumn
ASJC Scopus subject areas
- Electrical and Electronic Engineering
- Atomic and Molecular Physics, and Optics
- Analytical Chemistry