Patent ID: 8957565
Filing Date: 2015-02-17
Classification: H01L,H03H,Y10T

Abstract:
1. An acoustic wave device comprising: a piezoelectric substrate; a first electrode film arranged on a top surface of the piezoelectric substrate and defining electrodes including IDT electrodes; and a second electrode film arranged to extend from the top surface of the piezoelectric substrate to a portion of a top surface of the first electrode film; wherein the second electrode film defines electrodes including a wiring electrode and a pad electrode, and the second electrode film is defined by a layered metal film including a plurality of metal films deposited in layers; a lowermost layer of the layered metal film defining the second electrode film includes a metal selected from the group consisting of aluminum-copper alloy, nickel-chromium alloy, aluminum-silicon alloy, aluminum-titanium alloy, titanium, and copper; an upper layer of the layered metal film defining the second electrode film includes a top surface, a bottom surface, and side surfaces that extend between the top surface and the bottom surface; and the lowermost layer of the layered metal film defining the second electrode film is arranged to extend to and cover at least one of the side surfaces of the upper layer of the layered metal film defining the second electrode film.