Patent ID: 6462464
Filing Date: 2002-10-08
Classification: H01L

Abstract:
A stacked piezoelectric device comprising:a piezoelectric stack including piezoelectric layers adapted to extend and contract in accordance with the applied voltage, and internal electrode layers for supplying the applied voltage, each of said piezoelectric layers being stacked alternatively with the corresponding one of said internal electrode layers; and a first side electrode arranged on one side of the piezoelectric stack and a second side electrode arranged on the other side of the piezoelectric stack, the internal electrode layers being so configured that adjacent ones thereof with a piezoelectric layer therebetween are energized to different polarities by each side electrode; wherein the piezoelectric layers and the internal electrode layers are configured to have substantially the same area; wherein said internal electrode layers have the ends thereof exposed to the sides of the piezoelectric stack; wherein the first side electrode includes a plurality of first insulating portions formed to cover alternate ones of the ends of the internal electrode layers exposed to one side of the piezoelectric stack, a first conductive portion being arranged on said first insulating portions along the height of the piezoelectric stack; wherein the first side electrode energizes alternate ones of said internal electrode layers; wherein the second side electrode includes a plurality of second insulating portions formed to cover those alternate ones of the ends of the internal electrode layers which are exposed to the other side of the piezoelectric stack and not formed with said first insulative portions, a second conductive portion being arranged on said second insulating portions along the height of the piezoelectric stack; wherein said second side electrode energizes alternate ones of said internal electrode layers; wherein the first and second insulating portions are configured of an insulative resin; wherein the first and second conductive portions are configured of a conductive resin and formed to directly cover the ends of the internal electrode layers; and wherein the modulus of elasticity of said insulative resin and said conductive resin is 0.1 MPa to 40 GPa.