Method of cleaning workpiece with solvent and then with liquid carbon dioxide

摘要

A method for precision cleaning of a workpiece with a cleaning fluid comprising liquid and/or supercritical fluid carbon dioxide and a primary solvent which is liquid at ambient temperatures and pressures comprises first placing the workpiece in a pressurizable vessel with a removable lid and within an inner tank open at the top; supplying the primary solvent to the inner tank; flushing the primary solvent through the pressure vessel; draining the inner tank to remove the primary solvent; and then supplying liquid and/or supercritical fluid carbon dioxide to the pressure vessel and flushing it through the vessel by withdrawing it from near the bottom of the inner tank.