NEW INTERNAL STRESS DRIVEN ON-CHIP MICROMACHINES FOR EXTRACTING MECHANICAL PROPERTIES OF THIN FILMS

D. Fabrègue (1, 2) , Nicolas André (1, 3) , T. Pardoen (1, 2) , J.P. Raskin (1, 3)

1 CeRMiN, Research Center in Micro and Nanoscopic Materials and Electronic Devices
2 Dep. of Materials Science and Process
3 EMIC

A new concept of micromachines has been developed for measuring the mechanical properties of thin metallic films. The actuator is a beam undergoing large internal stresses built up during the deposition process. Al thin films are deposited partly on the actuator beam and on the substrate. By etching the structure, the actuator contracts and pulls the Al film. Full stress strain curves can be generated by designing a set of micromachines with various actuator lengths. In the present study, the displacements have been measured by scanning electronic microscopy. The stress is derived from simple continuum mechanics relationships. The tensile properties of Al films of various thicknesses have been tested. A marked increase of the strength with decreasing film thickness is observed.

Mots clés: Micromachines; thin films; internal stresses; microfabrication

Domaines: Architectures Matérielles [cs.AR]

D. Fabrègue, Nicolas André, T. Pardoen, J.P. Raskin. NEW INTERNAL STRESS DRIVEN ON-CHIP MICROMACHINES FOR EXTRACTING MECHANICAL PROPERTIES OF THIN FILMS. DTIP 2006, Apr 2006, Stresa, Lago Maggiore, Italy. 6 p. ⟨hal-00189284⟩