STRESS AND ELASTIC-CONSTANTS OF AMORPHOUS-GERMANIUM NITROGEN ALLOYS

Thermomechanical properties (stress, thermal expansion coefficient, an d elastic modulus) of a-GeNx:H thin films prepared by the rf sputterin g technique are reported. Stress measurements are made using a Dektak profilometer to determine the radius of curvature of the film/substrat e structure. The majority of the films prepared in this work have comp ressive stress. A second apparatus based on the deflection of a He-Ne laser beam is used to determine the thermal expansion coefficient and the Young's modulus/(1-Poisson's ratio) by the thermally induced bendi ng method. They depend strongly on the nitrogen concentration.