Samsung recently announced that it started mass producing the 64-bit Exynos Octa 7 using the 14-nm FinFET technology. The new chip is likely to be called the Exynos 7420, and is expected to power the upcoming Galaxy S6.
http://www.notebookcheck.net/Samsung-Exynos-Octa-7-enters-mass-production.136606.0.html