AVS 52nd International Symposium
    Plasma Science and Technology Thursday Sessions
       Session PS-ThA

Paper PS-ThA9
A Toroidal Plasma Source for Generation of High Throughput, Low Contamination Atomic Gases

Thursday, November 3, 2005, 4:40 pm, Room 304

Session: Plasma Sources and Equipment
Presenter: X. Chen, MKS Instruments, Inc.
Authors: X. Chen, MKS Instruments, Inc.
W.M. Holber, MKS Instruments, Inc.
P. Loomis, MKS Instruments, Inc.
J. Gunn, MKS Instruments, Inc.
S.Q. Shao, MKS Instruments, Inc.
Correspondent: Click to Email
A high power, low-field toroidal RF plasma source has been developed for generation of activated gases, such as O, H, N and F. In the plasma source, RF power is coupled through ferrite cores into the plasma that acts as a secondary of an RF transformer and is confined within a toroidal quartz chamber. A combination of toroidal plasma geometry, a quartz plasma chamber, and extremely low electric field (<8 V/cm) minimizes chamber surface erosion and associated contamination. More than twice as much of atomic oxygen is generated as compared with the current generation of remote plasma sources, resulting in 2-3 times increase in throughput for photoresist stripping. Other applications include gate dielectric modification, atomic layer deposition, annealing, and wafer cleaning. This paper characterizes the plasma source and its operation with O@sub 2@, N@sub 2@, H@sub 2@, H@sub 2@O, H@sub 2@/N@sub 2@ and H@sub 2@/He gasses. Experimental measurements of plasma density and atomic gas flux of O, N, and H, using Langmuir probes, recombination probes and calorimetry, are presented. Typical plasma density is in the order of 10@super 13@ cm@super -3@. Transport of the charged species and activated neutral species through quartz and sapphire ducts, materials commonly used as liners in semiconductor process chambers, are also reported.