Stresses in thin films and interconnect lines

The mechanical behavior of thin films and interconnect lines is investigated. Firstly, theoretical models of thermal stress evolution in thin films and passivated or unpassivated lines are considered. Secondly, the effect of texture in a copper thin film with a columnar grain structure is studied from a theoretical point of view. The film consists of three different constituents with (111), (100) and randomly oriented texture. Global properties as well as local stress distributions are considered in detail within a thermoelastic framework. The results are in qualitative agreement with available experimental results. Implications with regards to plastic behavior are briefly discussed. Finally, the potential of the curvature measurement technique for experimental stress evaluation in thin films is considered for initially flat and curved substrate/film systems. (C) 2002 Elsevier Science B.V. All rights reserved.