A stacked piezoelectric device, which is inexpensive and excellent in electric
transmission efficiency and little deterioration of strength of an internal electrode
layer, is provided by having an internal electrode layer containing not less than
50 percent by weight of Cu element, and not more than 5 percent of a pore occurrence
expressed by (B/A)100 (%) wherein A is an area of an interface between the
internal electrode layer and the piezoelectric layer and B is a sum of areas of
pores which appear in the interface and have a diameter of not less than 0.1 micrometers.
Preferably, a surface roughness Ra of the interface of the piezoelectric layer
contacting the internal electrode layer is not more than 0.5 C (m) wherein
C is a thickness of the internal electrode layer in micrometers. The piezoelectric
material constituting the piezoelectric layer preferably comprises PZT which is
a Pb(Zr,Ti)O3-based oxide having a perovskite structure.