WAFER LEVEL PACKAGE FOR SURFACE ACOUSTIC WAVE DEVICE AND FABLICATION METHOD THEREOF

摘要

A wafer level package for a SAW(Surface Acoustic Wave) device and a packaging method thereof are provided to reduce package size by using first and second via units having a different inner diameter. An SAW element(112) of an SAW device(110) is formed on an upper surface of a device wafer(111). A cap wafer is joined to an upper portion of the SAW device. The cap wafer has a via hole(H) that is passed through up and down. A conductive member(125) gap-fills a part of the via hole. The via hole has a first via unit(H1) and a second via unit(H2). The inside diameter of the first via unit becomes gradually narrow from a lower surface of the cap wafer up to a predetermined depth. The inside diameter of the second via unit becomes gradually widen from the first via unit up to an upper surface of the cap wafer.