Method for manufacturing surface acoustic wave apparatus

A method for manufacturing a surface acoustic wave apparatus comprising the steps of:

• a) forming an interdigital transducer (IDT) electrode and a connection line on an upper surface of a piezoelectric substrate, the IDT electrode being formed in a formation area on the piezoelectric substrate, the connection line for connecting the IDT electrode to an external circuit located outside of the surface acoustic wave device;
• b) forming a protective film after step a) and before step c), the protective film covering the formation area and at least an area where a frame member is to be disposed;
• c) forming the frame member on an upper surface of said protective film, the frame member surrounding the formation area and the frame member overlapping said connection line with the protective film between the frame member and the connection line in a thickness direction of the piezoelectric substrate;
• and
• d) forming a protective cover which is composed of said frame member and a lid member that covers said formation area and is configured for forming a space by connecting said lid member on said frame member, at least one of said frame member and said lid member being composed of resin, wherein one portion of the connection line is drawn outside the space.