Plasma Chemistry and Plasma Processing

, Volume 24, Issue 3, pp 353–372 | Cite as

Molecular Beam Mass Spectrometry System for Characterization of Thermal Plasma Chemical Vapor Deposition

  • Soonam Park
  • Feng Liao
  • John M. Larson
  • Steven L. Girshick
  • Michael R. Zachariah


A molecular beam mass spectrometry system for in situ measurement of the concentration of gas phase species including radicals impinging on a substrate during thermal plasma chemical vapor deposition (TPCVD) has been designed and constructed. Dynamically controlled substrate temperature was achieved using a variable thermal contact resistance method via a backside flow of an argon/helium mixture. A high quality molecular beam with beam‐to‐background signal greater than 20 was obtained under film growth conditions by sampling through a small nozzle (75 μm) in the center of the substrate. Mass discrimination effects were accounted for in order to quantify the species measurements. We demonstrate that this system has a minimum detection limit of under 100 ppb. Quantitative measurements of hydrocarbon species (H, H2, C, CH3, CH4, C2H2, C2H4) using Ar/H2/CH4 mixtures and silicon species (Si, SiH, SiH2, SiCl, SiCl2, Cl, HCl) using Ar/H2/SiCl4 mixtures were obtained under thermal plasma chemical vapor deposition conditions.


Thermal plasma chemical vapor deposition mass spectrometry 


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Copyright information

© Plenum Publishing Corporation 2004

Authors and Affiliations

  • Soonam Park
    • 1
  • Feng Liao
    • 1
  • John M. Larson
    • 2
  • Steven L. Girshick
    • 3
  • Michael R. Zachariah
    • 4
  1. 1.Department of Mechanical Engineering
  2. 2.Department of Mechanical Engineering
  3. 3.Department of Mechanical Engineering
  4. 4.Department of Mechanical Engineering

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