摘要 |
A piezoelectric and/or electrostrictive film element including a ceramic substrate (2, 22), and a piezoelectric or electrostrictive unit (18, 24) formed on the substrate and including a piezoelectric or electrostrictive layer (14, 42) between lower and upper electrodes (12, 40, 16, 44). The substrate has a window (6, 38) closed by a diaphragm portion (10, 26). The unit is disposed on the diaphragm portion such that at least one of the opposite ends of the unit is spaced apart from the edge of the window in a direction toward the center of the diaphragm portion. The end part of the diaphragm portion spaced apart from the edge of the window is upwardly convexed or downwardly concaved to provide a stress releasing section (20) for effectively converting stresses generated in the piezoelectric or electrostrictive unit into displacement of the diaphragm portion. Also disclosed are methods for forming the stress releasing section by firing the unfired piezoelectric/electrostrictive layer formed on the diaphragm portion of the fired ceramic substrate. <IMAGE> |