Intel has previewed the upcoming Lakefield SoC in a bit more detail in a new video. The video illustrates the new Foveros 3D packaging technology and how different heterogeneous components can be stacked on top of each other. This helps in reduced board footprint and consequently, enables thinner, lighter, more powerful devices.
https://www.notebookcheck.net/Intel-previews-the-Foveros-3D-packaging-technology-in-upcoming-Lakefield-hybrid-CPUs.410884.0.html