"The PZT film 18 is then coated with another layer 19 of conductive material, such as aluminum, nickel, chromium, platinum or ITO, and, as illustrated in FIG. 1(d), a photoresist layer 20 is coated on the conductive layer and then exposed to ultraviolet rays 21 through a mask 22 and developed to produce hardened regions 23." . . . .