US Patent 11549184 Coating of nano-scaled cavities

Methods, systems, and apparatus for coating the internal surface of nano-scale cavities on a substrate are contemplated. A first fluid of high wettability is applied to the nano-scale cavity, filling the cavity. A second fluid carrying a conductor or a catalyst is applied over the opening of the nano-scale cavity. The second fluid has a lower vapor pressure than the first fluid. The first fluid is converted to a gas, for example by heating the substrate. The gas exits the nano-scale cavity, creating a negative pressure or vacuum in the nano-scale cavity. The negative pressure draws the second fluid into the nano-scale cavity. The conductor is deposited on the interior surface of the nano-scale cavity, preferably less than 10 nm thick.