EFFECT OF INTERNAL-STRESS ON ADHESION AND OTHER MECHANICAL-PROPERTIES OF EVAPORATED INDIUM TIN OXIDE (ITO) FILMS

The relationship between various mechanical properties of evaporated indium tin oxide (ITO) films has been investigated. The hardness and internal stress were found to be correlated. This correlation can be expressed as a linear expression similar to that reported for a bulk material. The strength of adhesion to the substrate was observed to be related to the internal stress. This relationship was also linear and could be well interpreted quantitatively by assuming that the stored elastic energy in ITO films was constant during peeling. The coefficient of kinetic friction was found not to be related to any mechanical property. It depended only on the roughness of the film surfaces. A series of Taber abrasion tests revealed that the coefficient of friction was the most important for mechanical durability among factors such as hardness, adhesion, strength, and coefficient of friction.