A method includes forming a bump on a lower surface of an interposer. A first insulation layer is formed to cover the lower surface and bump. A trench is formed extending from the lower towards an upper surface of the interposer. A polymer supporting adhesive layer is formed to surround the bump and couples between the interposer and a semiconductor chip. The semiconductor chip has at least a sensing component and a conductive pad electrically connected to the sensing component, and the bump is connected to the conductive pad. A via is formed extending from the upper towards the lower surface. A second insulation layer is formed to cover the upper surface and the via. A redistribution layer is formed on the second insulation layer and in the via. A packaging layer is formed to cover the redistribution layer and has a second opening.