US 7,579,756 B2
Piezoactuator with low stray capacitance
Anke Althoff, St.-Andrä-Wördem (Austria); Adalbert Feltz, Deutschlandsberg (Austria); and Heinz Florian, Bad Gams (Austria)
Assigned to EPCOS AG, Munich (Germany)
Appl. No. 11/813,904
PCT Filed Jan. 18, 2006, PCT No. PCT/DE2006/000067
§ 371(c)(1), (2), (4) Date Aug. 24, 2007,
PCT Pub. No. WO2006/076894, PCT Pub. Date Jul. 27, 2006.
Claims priority of application No. 10 2005 002 428 (DE), filed on Jan. 18, 2005; and application No. 10 2005 018 791 (DE), filed on Apr. 22, 2005.
Prior Publication US 2008/0042522 A1, Feb. 21, 2008
Int. Cl. H01L 41/083 (2006.01)
U.S. Cl. 310—328 20 Claims
OG exemplary drawing
 
1. A piezoelectric actuator comprising:
a stack of piezoceramic layers;
electrodes among the piezoceramic layers;
wherein at least one edge region of the stack does not include electrodes; and
a cover layer at the at least one edge region, the cover layer having a dielectric constant that is less than a dielectric constant of a piezoceramic layer.