A high power microwave-driven plasma torch

Summary form only given. A plasma torch driven by either 2450 MHz or 915 MHz microwave radiation has been developed by PSI. The operates with internal pressures ranging from /spl sim/0.1 ATM to 12 ATM, and into both air and vacuum environments. It runs with a wide variety of gases, including N/sub 2/, air, O/sub 2/, SF/sub 6/, NF/sub 3/, CF/sub 4/, Cl/sub 2/ and He. The output of the torch is in the form of a jet with a measured temperature of 2000/spl deg/C-3000/spl deg/C. Devices at 2450 MHz and 915 MHz have been realized with powers to 5 kW and 16 kW, respectively. 915 MHz torches to 75 kW are planned. Measurements of the output jet show a high degree of dissociation for many gases, including SF, and oxygen. About 75% dissociation has been achieved with SF/sub 6/ resulting in a fluorine atom fluence of 3/spl times/10/sup 21//s for 2 kW operation. The high fluence output of the torch is attractive for many semiconductor processing applications. Details of the torch, its operation, and measurements of the output jet will be presented, as will comparisons with the results of modeling.