Hot-Stage Atomic Force Microscope for the Measurement of Plastic Deformation in Metallic Thin Films During Thermal Cycling

An Atomic Force Microscope is equipped with a hot-stage and a vacuum system in order to enable in-situ studies of plastic deformation and interfacial sliding of thin metallic films on Si substrates during thermal cycling. The apparatus can reach sample temperatures of lOO deg C while maintaining optimum resolution. The system will allow future in-situ thermal cycling experiments on microelectronic devices in a protected environment to provide insight into the role of plastic deformation in metallic thin films on the stability of future generations of device structures. The details of the design, along with the performance limitations of the system are discussed. Preliminary results demonstrating the performance of the system at an elevated temperature are presented. Limited post-situ results from direct measurement of the plastic deformation of thin Cu films on Si substrates induced by thermal cycling are also presented, primarily with the objective of establishing the need for detailed in-situ studies. While artifacts such as permanent dimensional changes of the film are observed post-situ, a detailed mechanistic understanding of the interaction between the temperature-dependent stress state of the film and the resultant inelastic deformation within the film and at the interface can only be obtained through in-situ experiments.Naval Postgraduate School Monterey CA is the author of 'Hot-Stage Atomic Force Microscope for the Measurement of Plastic Deformation in Metallic Thin Films During Thermal Cycling', published 2001 under ISBN 9781423527404 and ISBN 1423527402.