Die (110) are attached to an interposer (420), and the interposer/die assembly is placed into a lid cavity (510). The lid (210) is attached to the top of the assembly, possibly to the encapsulant (474) at the top. The lid's legs (520) surround the cavity and extend down below the top surface of the interposer's substrate (420S), possibly to the level of the bottom surface of the substrate or lower. The legs (520) may or may not be attached to the interposer/die assembly. In fabrication, the interposer wafer (420SW) has trenches (478) which receive the lid's legs during the lid placement. The interposer wafer is later thinned to remove the interposer wafer portion below the legs and to dice the interposer wafer. The thinning process also exposes, on the bottom, conductive vias (450) passing through the interposer substrate. Other features are also provided.

A package structure includes a first layer, a second layer and a third layer. The second layer includes an outer frame, a resonator and a chip. The second layer is arranged between the first layer and the third layer. The outer frame, the first layer and the third layer are constituted a rectangular accommodation portion. The resonator and the chip are located in the rectangular accommodation portion. The chip is located at a side of the resonator, and is electrically connected to the third layer and the resonator through a plurality of conductive components on the chip. A package structure in which the chip is located below the resonator is also provided.

A disclosed semiconductor structure may include an interposer, a first semiconductor die electrically coupled to the interposer, a packaging substrate electrically coupled to the interposer, and a capping layer covering one or more of a first surface of the first semiconductor die and a second surface of the packaging substrate. The capping layer may be formed over respective surfaces of each of the first semiconductor die and the packaging substrate. In certain embodiments, the capping layer may be formed only on the first surface of the first semiconductor die and not formed over the package substrate. In further embodiments, the semiconductor structure may include a second semiconductor die, such that the capping layer covers a surface of only one of the first semiconductor die and the second semiconductor die. The semiconductor structure may include a molding compound die frame that is partially or completely covered by the capping layer.