Abstract
We investigate the spectral response of nanostructured copper oxides thin film. Gold was doped in two different concentrations (2% and 4%) using the spray method. A novel ammonia gas sensor at various concentrations (0-500 ppm) was fabricated by replacing CuO films with a clad region. In addition, the effect of gold doping on structural, optical, and morphological properties has been demonstrated. The study shows that the spectral intensity increases linearly with ammonia concentration. The 4% Au doped CuO presents higher sensitivity compared with 2% doped and pure copper oxides. Time response characteristics of the sensor are also reported.