| 摘要 |
Under bump passive structures, such as capacitors and inductors, may be formed using the post-processing layers in wafer level packaging. In an embodiment, a packaged semiconductor device is described which includes an under-bump capacitor formed in semiconductor device post-processing layers. As part of the post-processing a first dielectric layer is deposited on the active face of a semiconductor die and then in sequence a first metal layer, second dielectric layer and second metal layer are deposited. The under-bump capacitor is formed from a lower plate in the first metal layer and an upper plate in the second metal layer, the plates being separated by the second dielectric layer. In order to increase capacitance, the capacitor may be formed over one or more openings in the first dielectric layer, such that the layers forming the capacitor are no longer planar but follow the underlying topology. |
