| AVS 55th International Symposium & Exhibition | |
| MEMS and NEMS | Monday Sessions |
| Session MN-MoM |
| Session: | Integrative Materials and Processes for MEMS/NEMS |
| Presenter: | Y.D. Kim, Seoul National University, South Korea |
| Authors: | Y.D. Kim, Seoul National University, South Korea J.H. Bak, Seoul National University, South Korea S.W. Cho, Seoul National University, South Korea B.Y. Lee, Seoul National University, South Korea S.R. Lee, Seoul National University, South Korea K. Char, Seoul National University, South Korea S. Hong, Seoul National University, South Korea Y.D. Park, Seoul National University, South Korea |
| Correspondent: | Click to Email |
We present evidence that the addition of Al-CNT lamina to suspended Al thin-film micromechanical resonators suppress anelastic effects. Addition of Al-CNT lamina to form a metallic-CNT nanolaminate has been shown to enhance mechanical properties, including elastic modulus as well as strengths, from dynamic and quasi-static flexural measurements of suspended doubly-clamped micromechanical beam resonator structures.1 In this study, dynamic flexural measurements for long loading-cycles (>1011) is presented. The micromechanical beam resonator structures, which are patterned by a combination of e-beam and photolithography methods, are fabricated from UHV sputter deposition of Al onto a self-assembled CNT network on a GaAs substrate, which is selectively removed to suspend the beam. The frequency response of the microresonators is periodically measured by a laser vibrometer-like set-up, while the beam is actuated electrostatically. For Al beam resonators, the resonance frequency (fo), which is directly related to the its elastic modulus, varies during the duration of measurement (Δfo/ fo <1.5%), while for Al-CNT beam resonators, fo is relatively unchanged for the duration. Such observations is consistent with the view that the CNTs mechanically reinforce and is well-incorporated in the Al thin-film, as anelastic effects are attributed to grain boundary sliding and are a contributor to stress relaxation in metallic thin-films.2
1 J.H. Bak, Y.D.Kim et al., Nature Materials advance online publication, 20 April 2008 (doi:10.1038/nmat2181).
2 S. Hyun et al., Appl. Phys. Lett. 87, 061902 (2005).