| 摘要 |
Substrates having a wide range of thickness, and intended to be overmolded with a plastic package body, are accommodated in a common mold. The top surface of the substrate is provided with a dam structure, which may be formed as an additional layer on the substrate, and which is preferably in the form of a square ring. A groove (channel) is machined (e.g., by routing) into the surface of the dam structure. The top mold half, having a cavity for forming the package body, is provided with a sealing structure at the periphery of the cavity. The sealing structure has a ridge fitting into the channel of the dam structure. The depth of the groove in the dam structure is readily adjusted to ensure uniform clamping pressure of the top mold half on the substrate, so that liquid molding compound is contained within the cavity and so that undue pressure is not exerted on the substrate. |
