A package structure is provided. The package structure includes a chip-containing structure over a substrate and a first adhesive element directly above the chip-containing structure. The first adhesive element has a first thermal conductivity. The package structure also includes multiple second adhesive elements directly above the chip-containing structure. The second adhesive elements are spaced apart from each other, each of the second adhesive elements has a second thermal conductivity, and the second thermal conductivity is greater than the first thermal conductivity. The package structure further includes a protective lid attached to the chip-containing structure through the first adhesive element and the second adhesive elements. The protective lid extends across opposite sidewalls of the chip-containing structure.

A diffusion soldering method for joining an electronic component to a substrate is provided. The joining surfaces are designed such that cavities are formed in a joining gap between the component and substrate. The formation of such cavities can be provided, e.g., by depressions in a mounting surface of the component and/or in a contact surface of the substrate, the depressions being cup-shaped and/or defining channels that surround columnar structural elements, the end faces of which define the mounting surface and/or contact surface. The cavities are designed such that solder material can leak into the cavities when the component during a heating process to achieve a desired width of the joining gap. This allows for the formation of a narrow-width joining having a diffusion zone that bridges the joining gap upon soldering. In this manner, a diffusion solder connection can be produced even using standard solder.

Semiconductor devices with underfill control features, and associated systems and methods. A representative system includes a substrate having a substrate surface and a cavity in the substrate surface, and a semiconductor device having a device surface facing toward the substrate surface. The semiconductor device further includes at least one circuit element electrically coupled to a conductive structure. The conductive structure is electrically connected to the substrate, and the semiconductor device further has a non-conductive material positioned adjacent the conductive structure and aligned with the cavity of the substrate. An underfill material is positioned between the substrate and the semiconductor device. In other embodiments, in addition to or in lieu of the con-conductive material, a first conductive structure is connected within the cavity, and a second conductive structure connected outside the cavity. The first conductive structure extends away from the device surface a greater distance than does the second conductive structure.

A package structure is provided. The package structure includes a chip structure and a first adhesive element partially covering the chip structure. The first adhesive element has a first portion and a second portion, and the first portion is spaced apart from the second portion. The first adhesive element has a first thermal conductivity. The package structure also includes a second adhesive element partially covering the chip structure. The second adhesive element has a second thermal conductivity, and the second thermal conductivity is higher than the first thermal conductivity.