Methods and materials
- Ultra-long lifetime electrode materials: SrRuO3 and other oxide electrodes
- Deposition technique: pulsed laser deposition and solution deposition (sol-gel)
- Film thickness: nanometers to micrometers
- Film growth: polycrystalline, textured and epitaxial
- Wafer diameter: 10 to 150 mm
- Packaging: thermal, electronic and fluidic interfacing
Piezoelectric materials used are:
- Lead-based materials: Pb(Zr,Ti)O3 (PZT) and Pb(Mg1/3Nb2/3)O3-PbTiO3 (PMN-PT)
- Lead-free materials: BaTiO3 (BTO), Ba0.5Sr0.5TiO3 (BST), K0.5Na0.5NbO3 (KNN), (K,Na)0.5Bi0.5TiO3 (KNBT), BiFeO3 (BFO)
Several important functional parameters of Piezo MEMS devices:
Films | Pr (µC/cm2)* | er | d33 (pm/V) | -e31 (C/m2) | EBD (kV/cm) |
Lead-based | 20-40 | 800-2200 | 100-400 | 10-18 | 800-2500 |
Lead-free | 15-30 | 500-1500 | 50-250 | 6-14 | 500-1500 |
* Pr: remanent polarization; er: dielectric constant; d33 and e31: longitudinal and transverse piezoelectric coefficients, respectively; EBD: breakdown electric field.