AVS 46th International Symposium
    Plasma Science and Technology Division Friday Sessions
       Session PS-FrM

Paper PS-FrM11
Characterizations of a Compact, Low-Field Toroidal Plasma Source for Downstream Plasma Processing

Friday, October 29, 1999, 11:40 am, Room 609

Session: Emerging Plasma Applications
Presenter: X. Chen, Applied Science and Technology, Inc.
Authors: X. Chen, Applied Science and Technology, Inc.
W.M. Holber, Applied Science and Technology, Inc.
D.K. Smith, Applied Science and Technology, Inc.
M.G. Blain, Sandia National Laboratories
R.L. Jarecki, Sandia National Laboratories
Correspondent: Click to Email
Activated atomic gases are used in semiconductor processing for applications including photoresist strip, passivation and chemical vapor deposition (CVD) chamber clean. We report the production of activated atomic fluorine, oxygen, nitrogen and hydrogen using a low-field toroidal (LFT@super TM@) downstream plasma source. The ASTRON@super TM@ reactive gas generator uses an electrodeless toroidal plasma source design, in which the rf power supply is integrated directly into the same enclosure as the plasma source. It operates at pressures from a few millitorr to one atmosphere. Typical plasma density is 3x10@super 13@ cm@super -3@. Thorough characterization of the plasma source is conducted using working gases such as NF@sub 3@, CF@sub 4@, CHF@sub 3@, C@sub 3@F@sub 8@, SF@sub 6@, O@sub 2@, N@sub 2@, NH@sub 3@ and H@sub 2@. The production and transport of the atomic species are investigated using chemiluminescent titration and etch rate measurements of silicon dioxide and photoresist. Greater than 90% of NF@sub 3@ is dissociated at flow rates of over 2 slm. The etch rates of SiO@sub 2@, SiN, WN, W and TiN are measured. Adding argon to an O@sub 2@/N@sub 2@ plasma increases the production of atomic oxygen and the rate of photoresist strip while not raising the power consumption. Contamination and particle measurements show that the plasma source is compatible with semiconductor processing. @FootnoteText@ Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy under Contract No. DE-AC04-94AL85000.