Deposition of functional PZT films as actuators in MEMS devices by high rate sputtering
H.-J. Quenzer, R. Dudde, H. Jacobsen, B. Wagner, H. Föll
Fraunhofer ISIT, DE
actuator, MEMS, PZT, gas flow sputtering
Crack and void free polycrystalline Lead Zirconate Titanate (PZT) films in the range of 5 µm to 10 µm have been successfully deposited on silicon substrates using a novel high rate gas flow sputtering process. Deposition rates of 200-250 nm/min were observed. These high sputter rates are about 20 - 25 times higher than reported from reactive magnetron sputtering and demonstrate the potential of this sputter technique. Based on this deposition process a membrane actuator consisting of a SOI layer and a sputtered PZT thin film was prepared. The sputtered PZT layers show a high dielectric constant er between 1000 and 1800 and a distinct ferroelectric hysteresis loop with a remanent polarisation of 17 µC/cm2 and a coercive field strength of 5.4 kV/mm.
Nanotech 2008 Conference Program Abstract