Abstract
Stresses in micro electro mechanical system (MEMS) multilayer structures with SiO2/Pt/Pb(Zr,Ti)O3/Pt thin-film stacks on Si substrates were investigated by measuring the radius of wafer curvature for each film. The SiO2 film and Pt electrodes were under compressive stress and Pb(Zr,Ti)O3 film was under tensile stress prior to subsequent depositions. However, the stresses in each film after the last coating were tensile, except in the Pt top electrode. The interactions between different films in the multilayer were also studied by measuring the radius of curvature as each film was wet-etched layer by layer. Furthermore, the beams were fabricated using a microfabrication process to investigate the curving state of a multilayer structure released from the Si substrate. The curving states of beams are related to not only the stresses in each film but also the balance of flexural rigidity among films. A beam without any curvature was successfully obtained by adjusting the thickness of each film.
| Original language | English |
|---|---|
| Pages (from-to) | 1386-1390 |
| Number of pages | 5 |
| Journal | Japanese Journal of Applied Physics |
| Volume | 42 |
| Issue number | 3 |
| DOIs | |
| State | Published - Mar 2003 |
| Externally published | Yes |
Keywords
- Flexural rigidity
- MEMS
- Multilayer structure
- Radius of curvature
- Residual stress