Hugo Enrique Lazcano Hernández, Celia A. Sanchez Perez, Augusto García Valenzuela,
2008
Publicado con arbitraje
An optically integrated NH3 sensor using WO3 thin films as sensitive material
J. Opt. A: Pure Appl
J. Opt. A: Pure Appl. Opt. 10 104016
FISICA
OPTICA
OPTICA FISICA
We analyze the optical response of WO3 sputtered thin films to NH3 gas sensing through transmittance changes. By sputtering, films with a combination of the monoclinic and triclinic crystalline structures were obtained. The films show sensitivity to NH3 presence at the wavelengths ? = 980 nm and 1550 nm and at low temperature, T = 90?°C. The optical constants (refractive index (n) and absorbant coefficient (?)) were calculated using the transmittance spectra and the model of a simple resonator. According to these results, an integrated optical NH3 sensor based on a glass waveguide with a WO3 thin film deposited at the surface was designed and experimentally characterized.