EN
In the paper results of investigation of the influence of low concentration hydrogen on stress changes in thin catalytic metal films were discussed. The concentration of H2 was altered from 6 ppm to 1% of hydrogen (6N) in nitrogen (6N). Silicon beams covered with palladium or platinum films of various thicknesses were anchored at one end and their deflection at the other end was measured by atomic force microscope. Stress changes were determined by application of modified Stoney formula and compared with results of computer modelling. The influence of stress caused by hydrogen absorption on the alteration of output characteristics of AIII-N based hydrogen sensors was excluded. The time dependence of stress in metallic films for various hydrogen concentrations indicated dissociation limited mechanism of hydrogen absorption.