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.