7 nm node jump takes less precedence over 3 dimensional stacked semiconductor fabrication. The cloud and 5G helping to outsource high performance computing to servers from the nodes. Due to this offloading of computing, 14 nm processors, even a 28nm chips in many cases can handle much of the processing requirements in mobile phones and any such hand held wearable devices. A good example of such trend is design of Apple's A10 chip for iPhone7.
Use of the such technologies is even more significant for wearables, where the available space is no more than a area of wristwatch, if there is any integration, it has to be three-dimensional. A wearable electronics device need to have application processor SOC chip, solid-state memory such as DRAM, flash memory, RF and power management. The best way to achieve such integration is by using three-dimensional package on package technology to pack all this vertically and connect them through silicon vias. Samsung is delivering such a device exclusively for wearables, which is now in mass production.
The 14 nm Exynos 7 Dual 7270 mobile application processor integrates, Wi-Fi, Bluetooth and Cat.4 LTE 2CA modem, allowing the chip to connect to cellular service as a standalone device and also enabling device to device data transferring and Internet connectivity through Wi-Fi tethering. The two Cortex-A53 cores in the Exynos 7270 deliver 20 percent improvement in power efficiency compared to 28nm. FM radio and GPS is also made available in this chip.
SiP(system-in-package)-ePoP(embedded package-on-package) stacks application processor, DRAM and NAND flash memory chips and also the power management IC in a single 3D package.
For developers Samsung is offering reference design platform based on this chip Exynos 7270, NFC (near field communication) and various sensors for speed up the development.