| 摘要 |
PROBLEM TO BE SOLVED: To provide a surface acoustic wave device which reduces the influence of stress due to the coefficient difference of thermal expansion between a surface acoustic wave chip and a circuit board and prevents a connection failure caused by heat from being generated. SOLUTION: When crystal is used for a surface acoustic wave substrate K1 and alumina is used for a circuit board, bumps 10 to 19 are arranged in a certain fixed area B1 for aluminum pads (an input electrode pad 4, an output electrode pad 5 and ground electrode pads G1 to G8) existing on the function surface of a surface acoustic wave chip 1. According to this, an area where the bumps 10 to 19 are formed, the film thickness (Al film thickness) of the aluminum pads, the chip size of the surface acoustic wave chip 1 and the number of bumps are regulated for a crystal or LiTaO3 surface acoustic wave substrate. |
