COMPOSITE FILTER CHIP

PROBLEM TO BE SOLVED: To achieve a filter chip which can control the footprint, in an apparatus employing a plurality of filter chips. SOLUTION: The composite filter chip comprises a laminated chip 31, consisting of a first filter chip 11 and a second filter chip 21 mounted on a mounting substrate 41. The first filter chip 11 consists of a filter circuit 12 formed on the major surface of a silicon substrate, and a plurality of pads 13 connected electrically with the filter circuit 12. Similarly, the second filter chip 21 consists of a filter circuit 22, formed on the major surface of the silicon substrate, and a plurality of pads 23 formed on the opposite sides of the filter circuit 22 at an interval. Each pad 23 is connected electrically with the filter circuit 12. The first filter chip 11 and the second filter chip 21 are bonded, while made to face the back side of the silicon substrate to each other. COPYRIGHT: (C)2007,JPO&INPIT