Jet-REMPI is a technique used for the detection of trace aromatic vapors. Opotek are developing an instrument based on their tunable OPO technology that is a highly-sensitive, real-time device for the detection of a variety of species with high chemical sensitivity. By providing rapid measurements of process contaminants, this instrument will yield timely information for process optimization resulting increased yields. With a target detection limit of ~100 ppt for a wide variety of vapors, including most common aromatic solvents, the system will be able to provide highly sensitive monitoring of trace contaminants in the clean-room environment.