Chemical Vapor Deposition

Cover image for Chemical Vapor Deposition

January, 2004

Volume 10, Issue 1

Pages 3–4

    1. Contents: Chem. Vap. Deposition 1/2004 (pages 3–4)

      Version of Record online: 29 JAN 2004 | DOI: 10.1002/cvde.200490000

    2. Developments with CVD (page 7)

      M.L. Hitchman

      Version of Record online: 29 JAN 2004 | DOI: 10.1002/cvde.200490002

      Read how CVDis growing and developing to meet the needs of authors and readers alike.

    3. Synthesis of Monodisperse Ultrapure Gallium Nitride Nanoparticles by MOCVD (pages 11–13)

      Y. Azuma, M. Shimada and K. Okuyama

      Version of Record online: 29 JAN 2004 | DOI: 10.1002/cvde.200304158

      Nanoparticles of GaN are synthesized by MOCVD. The TEM analysis of the yellowish powder shows nanoparticles of 6.4 nm diameter and arithmetic standard deviation of 1.4 nm (see Figure). Results from elemental and SAED analyses reveal that the nanoparticles are virtually stoichiometric GaN with hexagonal crystallinity. Particle photoluminescence exhibits a peak at 370 nm which is at approximately the same wavelength produced by bulk GaN.

    4. Growth of Lanthanum Oxide Thin Films by Liquid Injection MOCVD Using a Novel Lathanum Alkoxide Precursor (pages 13–17)

      H.C. Aspinall, J. Gaskell, P.A. Williams, A.C. Jones, P.R. Chalker, P.A. Marshall, L.M. Smith and G.W. Crichlow

      Version of Record online: 29 JAN 2004 | DOI: 10.1002/cvde.200304164

      Carbon-free lanthanum oxide is deposited by liquid injection MOCVD over a wide temperature range (300–600 °C) in the presence of oxygen using a new volatile lanthanum alkoxide precursor [La(mmp)3]. SEM of a typical lanthanum oxide film deposited at 450°C from a [La(mmp)3]/tetraglyme mixture in toluene reveals a columnar growth structure with XRD reflection pattern and intensity approximately consistent with that of La2O3 powder. The paper suggests the suitability of this low temperature process for the deposition of high-κ lanthanum oxide films as gate dielectric for Si-based TFTs.

    5. A Novel PECVD Procedure for the Room-Temperature Synthesis of SiO2 Thin Films with Controlled Porosity (pages 17–20)

      A. Barranco, J. Cotrino, F. Yubero, J.P. Espinós, L. Contreras and A.R. González-Elipe

      Version of Record online: 29 JAN 2004 | DOI: 10.1002/cvde.200304149

      Room-temperature synthesis of porous SiO2 is achieved using a novel PECVD procedure. Porosity of the films is found to directly correlate with the thickness of a sacrificial polymer layer which is removed during the deposition of the oxide thin film. Films prepared with this method (see Figure) are transparent with low refractive index and are very well suited for antireflective coatings and other related optical applications. Membrane-like layers can also be prepared by this method.

    6. Vapor Pressures of Precursors for the Chemical Vapor Deposition of Silicon-Based Films (pages 20–22)

      G.R. Alcott, R.M.C.M. van de Sanden, S. Kondic and J.L. Linden

      Version of Record online: 29 JAN 2004 | DOI: 10.1002/cvde.200306145

      Thermal stability and vapor pressure measurement for a number of SiO2 precursors are studied. For the first time results from1,2-bis(trimethyl)siloxyethane (TMSE), (3-glycidoxypropyl) trimethylethoxysilane (Glymol) and 1H,1H, 2H, 2H-perfluorooctyltriethoxysilane (PTES) are reported. Results from tetraethoxysilane (TEOS), tripropylsilane (TPS) are found to agree with previously published values. Measurements are made in the temperatures range of 20 to 200 °C and values are fitted using the integrated Clausius–Claperon equation. Enthalpies of vaporization are calculated.

    7. Fabrication and Properties of Tantalum Film Deposited on Titanium through LP-CVD from TaCl5-H2 (pages 23–28)

      A. Levesque and A. Bouteville

      Version of Record online: 29 JAN 2004 | DOI: 10.1002/cvde.200306204

      Tantalum films are deposited on titanium substrates in a hot wall LPCVD system from TaCl5–H2. Depositions carried out at Tsubstrate = 800 °C and Ptotal = 332.5 Pa produce well-crystallized Ta films which contain the two phases α-Ta and β-Ta. No chlorine incorporation is found but some oxygen is detected at the surface of the deposit and at the Ti–Ta interface. Ta layers deposited (see Figure) are conformal and ensure excellent protection of the Ti substrate against acidic environments.

    8. Growth of Thin Films of Molybdenum and Tungsten Oxides by Combustion CVD Using Aqueous Precursor Solutions (pages 29–34)

      M.J. Davis, G. Benito, D.W. Sheel and M.E. Pemble

      Version of Record online: 29 JAN 2004 | DOI: 10.1002/cvde.200306260

      Combustion CVD has been used to deposit molybdenum and tungsten oxide layers on glass and silicon at low substrate temperatures using aqueous solutions of inexpensive salts of molybdate and metatungstate ions. The solutions are delivered to the coating flame as an aerosol from an ultrasonic nebuliser. Growth at low temperatures is found to produce amorphous films of pure oxide with stoichiometries close to those of the trioxides. Careful selection of the growth parameters allows the growth of continuous, moderately smooth, disordered molybdenum and tungsten oxide films which might be suitable for a variety of industrial coating applications.

    9. Deposition of Antimony and Antimony Oxides by MOCVD (pages 35–44)

      C.P. Myers, P.W. Haycock, M. Pichot, G.A. Horley, K.C. Molloy, S.A. Rushworth and L.M. Smith

      Version of Record online: 29 JAN 2004 | DOI: 10.1002/cvde.200306267

      Thin films of antimony and antimony oxide are prepared by MOCVD from a variety of precursors in the temperature range 150–650 °C under both atmospheric and reduced pressure. Below 400 °C uniform films of pure senarmontite (Sb2O3) are deposited with a microstructure and crystal structure that is strongly dependent on the deposition temperature. Above 400° C mixed-phase material is produced with isolated crystals of pure antimony (see Figure). Addition of oxygen leads to the production of higher antimony oxidation states.

    10. CuInS2 Thin Films Deposited by ALD (pages 45–49)

      M. Nanu, L. Reijnen, B. Meester, J. Schoonman and A. Goossens

      Version of Record online: 29 JAN 2004 | DOI: 10.1002/cvde.200306262

      Atomic layer deposition of CuInS2 is achieved on TiO2, glass, and SnO2:F-coated glass substrates in the pressure range of 2–10 mbar and temperature range of 350–500 °C using CuCl, InCl3, and H2S as precursors. Deposition temperature and pulse length are found to be the decisive parameters influencing film properties. The morphology and film composition are investigated with SEM, XRD, RBS, and Raman spectroscopy. Results indicate that, depending on the process conditions, CuInS2 single phase, Cu-poor (mixture of CuInS2 and CuIn5S8) or Cu-rich (mixture of CuxS and CuInS2) phases are formed.