What is Microsoft in-chip microfluidic cooling (with Corintis)?

Microsoft's in-chip microfluidic cooling, developed with Corintis, etches branching channels directly into the back of a silicon die so coolant flows in direct contact with the chip itself, rather than through a separate cold plate. This removes heat closer to its source and yields warmer, higher-grade waste heat that can potentially be reused rather than simply vented.