Patent ID: 7274129

Claim:
A surface acoustic wave device comprising: a first substrate; a surface acoustic wave chip attached to the first substrate; and a second substrate that hermetically seals the surface acoustic wave chip, the first substrates comprising one of silicon and sapphire as a major component, and the second substrate comprising silicon as a major component, the first and second substrates having joining surfaces processed by a surface activation process, an electric circuit being formed on a surface area of the second substrate other than the joining surfaces and facing the surface acoustic wave chip, the second substrate having second electrode pads electrically connected to first electrode pads formed on the surface acoustic wave chip, the surface acoustic wave chip having a back surface attached to a surface of the first substrate by another surface activation process, the first and second electrode pads facing each other and being bonded, so that the surface acoustic wave chip can be mechanically and electrically connected to the second substrate.