AVS 47th International Symposium
    Plasma Science and Technology Tuesday Sessions
       Session PS2-TuA

Paper PS2-TuA7
Development of an Instrument: Resonantly Enhanced Multiphoton Ionization of Radicals Detected Using Time of Flight Mass Spectrometry

Tuesday, October 3, 2000, 4:00 pm, Room 311

Session: Plasma Diagnostics I
Presenter: W.C. Flory, Colorado State University
Authors: W.C. Flory, Colorado State University
K.L. Williams, Colorado State University
E.R. Fisher, Colorado State University
Correspondent: Click to Email
Plasma deposition and etching mechanisms have been studied extensively in recent years due to the technological utility of low-temperature plasmas. Much remains to be done on a molecular level, however, before a complete understanding of the underlying chemistry is gained. To this end, we have designed and constructed a molecular beam apparatus employing resonantly enhanced multiphoton ionization (REMPI) to examine the production and reactivity of radical species in low temperature plasmas. This newly constructed plasma molecular beam apparatus builds on our past experiments employing laser-induced fluorescence (LIF) to study the surface reactivity of plasma radicals. The REMPI instrument has been employed to study SiF radicals produced in a SiF@sub 4@ plasma. The SiF radicals are detected using [2+1] REMPI combined with time of flight mass spectrometry (TOFMS). The absorption band from the (1,0) C@super"2@@SIGMA@@super+@ <-- X@super2@@PI@@sub1/2@ transition of the SiF molecule was monitored. Production of SiF in the plasma has been measured as a function of plasma parameters, including addition of H@sub2@ and O@sub2@, and applied rf power. In addition to results for SiF, comparisons will be made to fluorocarbon radicals (CF, CF@sub3@) and to other silicon-containing species (e.g. SiH@sub2@, SiH@sub3@). Preliminary results from these systems will be presented.