Adhesion properties of Cu-multilayers in electronic devices

Abstract

Delamination related failure caused by thermo- mechanical stress poses a critical problem in the reliability of microelectronic components. Microelectronic components contain multilayered Si- thin film structures where different material layers are attached to one another. Differing material properties of these thin film layers lead to internal stresses in the interfaces which, in combination with thermo- mechanical stress, result in delamination. This subsequently means that investigation of delamination behavior and adhesion properties is pivotal in prediciting the lifetime of microelectronics. Despite the importance of this issue, research on delamination of thin film structures is still not sufficient, thus impairing the development of new functions and technologies. The objective of this master thesis was to investigate the delamination behavior and adhesion properties of various thin films in multilayered Si- Cu structures through four- point bending tests and to determine the corresponding energy release rates (G). The main focus of the study was to analyze the effect of temperature and atmosphere on the interfacial toughness of Polyimide- Cu interfaces. Furthermore the influence of sample geometry (trench structure) on delamination toughness of Si- Cu interfaces and the impact of process parameters on industrially relevant samples were investigated.