Abstract: A system and process for liquefying a gas, comprising introducing a feed stream into a liquefier comprising at least a warm expander and a cold expander; compressing the feed stream in the liquefier to a pressure greater than its critical pressure and cooling the compressed feed stream to a temperature below its critical temperature to form a high pressure dense-phase stream; removing the high pressure dense-phase stream from the liquefier, reducing the pressure of the high pressure dense-phase stream in an expansion device to form a resultant two-phase stream and then directly introducing the resultant two-phase stream into a storage tank; and combining a flash portion of the resultant two-phase stream with a boil-off vapor from a liquid in the storage tank to form a combined vapor stream, wherein the temperature of the high pressure dense-phase stream is lower than the temperature of a discharge stream of the cold expander.

Abstract: The present invention is a process for cleaning a reaction chamber comprising the steps of; (a) Providing a reaction chamber to deposit materials on a target substrate; (b) Depositing the materials on the target substrate in an interior of the reaction chamber; (c) Periodically discontinuing the depositing, and contacting the reaction chamber interior with a mixture of fluorine and nitrogen to clean the interior of the reaction chamber; and, (d) when the mixture of fluorine and nitrogen is not available, switching to contacting the reaction chamber interior with nitrogen trifluoride. An apparatus is also disclosed.