Tag: CVD

Nitrogen CVD precursors

Ammonia NH3

  • Melting point -77.75°C
  • Boiling point -33.42°C
  • Critical temperature 132.3°C
  • Critical pressure 11.3 MPa
  • Molar mass  17.03 g/mol
Ammonia saturated vapor pressure
Ammonia saturated vapor pressure

Hydrazine N2H4

  • Melting point 2°C
  • Boiling point 113.5°C
  • Condensed phase density 1.008g/cm3 (at 20°C)
  • Molar mass 32.05 g/mol
Hydrazine saturated vapor pressure
Hydrazine saturated vapor pressure

Stull, D. R. (1947). Inorganic compounds. Industrial & Engineering Chemistry, 39(4), 540-550.

Scott, D. W., Oliver, G. D., Gross, M. E., Hubbard, W. N., & Huffman, H. M. (1949). Hydrazine: Heat capacity, heats of fusion and vaporization, vapor pressure, entropy and thermodynamic functions. Journal of the American Chemical Society, 71(7), 2293-2297.

Silicon CVD precursors

Halide Precursors

Silicon Tetrachloride SiCl4

  • Melting point -68.9°C
  • Boiling point 57.0°C
  • Condensed phase density 1.48g/cm3 (at 20°C)
  • Molar mass 169.9 g/mol
SiCl4 saturated vapor pressure
SiCl4 saturated vapor pressure

Silicon Tetrafluoride SiF4

  • Melting point -86.8°C
  • Boiling point -65.0°C
  • Critical temperature -14.15°C
  • Critical pressure 3.75 MPa
  • Molar mass 169.9 g/mol

 

Hexachlorodisilane Si2Cl6

  • Melting point -1°C
  • Boiling point 144°C
  • Condensed phase density 1.56g/cm3 (at 25°C)
  • Molar mass 268.9 g/mol
Si2Cl6 saturated vapor pressure
Hexachlorodisilane (Si2Cl6) saturated vapor pressure

 

Stull, D. R. (1947). Inorganic compounds. Industrial & Engineering Chemistry, 39(4), 540-550.

 

Boron CVD precursors

Halide precursors

Boron Trifluoride BF3

  • Melting point  -128°C
  • Boiling point -100°C
  • Critical temperature -12.3°C
  • Critical pressure 4.99 MPa
  • Molar mass 67.81 g/mol

Boron Tricloride BCl3

  • Melting point  -107°C
  • Boiling point  12.5°C
  • Critical temperature 178.8°C
  • Critical pressure 3.87 MPa
  • Molar mass 117.17 g/mol
Boron Trichloride (BCl3) saturated vapor pressure
Saturated vapor pressure of Boron Trichloride BCl3

 

Gallium Nitride

Halide/Hydride vapor phase epitaxy

Gallium Monochloride precursor

In typical HVPE process for GaN deposition gallium monochloride GaCl and ammonia NH3 are used as precursors of gallium and nitrogen:

GaCl+NH3=GaN+HCl+H2

The reaction is exothermic, and the reaction driving force decreases with increasing temperature:

GaCl + NH3 = GaN + HCl + H2 Gibbs Energy and Enthalpy
GaCl + NH3 = GaN + HCl + H2 deposition reaction equilibrium constant

Typical deposition temperature for epitaxial growth is 800-1100°C. At lower temperatures the deposition rate decreases due to reaction kinetic limitation, at higher temperatures the deposition rate decreases as a result of a decrease in supersaturation:

GaN HVPE deposition rate temperature dependence
GaN HVPE deposition rate temperature dependence

Gallium trichloride precursor

GaN deposition by  reaction of gallium trichloride GaCl3 and ammonia

GaCl3 + NH3 = GaN + 3HCl

is endothermic and the reaction driving force increases with increasing temperature, that makes possible to deposit GaN at temperatures 1300-1400°C:

GaCl3 + NH3 = GaN + 3HCl reaction Gibbs free energy and enthalpy
GaCl3 + NH3 = GaN + 3HCl reaction equilibrium constant

 

Maruska, H. P. and Tietjen, J. J., “The preparation and properties of vapor-deposited single-crystalline GaN”, Applied Physics Letters 15, 10 (1969), pp. 327-329.

Ban, Vladimir S., “Mass Spectrometric Studies of Vapor-Phase Crystal Growth II.”, Journal of the Electrochemical Society 119, 6 (1972), pp. 761–765.

Seifert, W. and Fitzl, G and Butter, E., “Study on the growth rate in VPE of GaN”, Journal of Crystal Growth 52 (1981), pp. 257–262.

Fornari, R. and Bosi, M. and Armani, N. and Attolini, G. and Ferrari, C. and Pelosi, C. and Salviati, G., “Hydride vapour phase epitaxy growth and characterisation of GaN layers”, Materials Science and Engineering: B 79, 2 (2001), pp. 159–164.

Usui, A., “Bulk GaN crystal with low defect density grown by hydride vapor phase epitaxy”, дюйм MRS Proceedings vol. 482, no. 1 (, 1997).

Malinovsky, V. V. and Marasina, L. A. and Pichugin, I. G. and Tlaczala, M., “The Growth Kinetics and Surface Morphology of GaN Epitaxial Layers on Sapphire”, Crystal Research and Technology 17, 7 (1982), pp. 835–840.

Koukitu, Akinori and Mayumi, Miho and Kumagai, Yoshinao, “Surface polarity dependence of decomposition and growth of GaN studied using in situ gravimetric monitoring”, Journal of Crystal Growth 246, 3 (2002), pp. 230–236.

Murakami, H., Takekawa, N., Shiono, A., Thieu, Q. T., Togashi, R., Kumagai, Y., … & Koukitu, A. (2016). Tri-halide vapor phase epitaxy of thick GaN using gaseous GaCl3 precursor. Journal of Crystal Growth, 456, 140-144.

Chemical vapor deposition reactions

Pure elements

  • Transition metal film:  Ti, Mo, W, Nb, Re, Ta, Zr, Hf
  • Non-metal film: B, C, Si, Ge

Binary compounds

  • Carbides: B4C, SiC, TiC, WC, HfC, NbC, TaC, VC, ZrC
  • Silicides: MoSi2, WSi2, TiSi2, V3Si, Nb3Si
  • Nitrides: BN, AlN, GaN, TiN, VN, ZrN, HfN, TaN, NbN, Si3N4, Ge3N4, FexN
  • Oxides: Al2O3, Ga2O3, SiO2, HfO2, Ta2O5, Nb2O5, SnO2, TiO2, ZrO2
  • Borides:  TiB2, ZrB2, HfB2
  • Chalcogenides:  MoS2, WS2, MoSe2, WSe2

Vanadium CVD precursors

Halide precursors

Vanadium pentafluoride VF5

  • Melting point 19.5°C
  • Boiling point 48°C
  • Condensed phase density 2.48 g/cm3  (at 20°C)
  • Molar mass   145.9 g/mol
Saturated vapor pressure of VF5
Saturated vapor pressure of Vanadium Pentafluoride VF5

Vanadium tetrachloride VCl4

  • Melting point -20.5°C
  • Boiling point 153°C
  • Condensed phase density 1.82 g/cm3  (at 25°C)
  • Molar mass   192.75 g/mol
Saturated vapor pressure of VCl4
Saturated vapor pressure of Vanadium Tetrachloride VCl4

 

 

Clark, H. C., & Emeléus, H. J. (1957). 406. Some physical and chemical properties of vanadium pentafluoride. Journal of the Chemical Society (Resumed), 2119-2122.

Trevorrow, L. E., Fischer, J., & Steunenberg, R. K. (1957). The Preparation and Properties of Vanadium Pentafluoride1. Journal of the American Chemical Society, 79(19), 5167-5168.

Cavell, R. G., & Clark, H. C. (1963). DENSITY, VISCOSITY, AND SURFACE TENSION OF VANADIUM PENTAFLUORIDE. JOURNAL OF THE CHEMICAL SOCIETY, (AUG), 4261.

Tantalum CVD Precursors

Halide Precursors

Tantalum Pentafluoride TaF5

  • Melting point 96°C
  • Boiling point 229.2°C
  • Condensed phase density  4.98 g/cm3 (at 15°C),  3.88 g/cm3 (at melting point)
  • Molar mass   275.9 g/mol
Saturated vapor pressure over liquid TaF5
Saturated vapor pressure over liquid TaF5

Tantalum Pentachloride TaCl5

  • Melting point 216.5°C
  • Boiling point 236°C
  • Condensed phase density 3.68  g/cm3 (at 28°C), 2.68  g/cm3 (at melting point)
  • Molar mass  358.2  g/mol
Saturated vapor pressure over TaCl5
Saturated vapor pressure over TaCl5

Fairbrother, F., Grundy, K. H., & Thompson, A. (1965). 121. The halides of niobium and tantalum. Part VIII. The densities, viscosities, and self-ionisation of niobium and tantalum pentafluorides. Journal of the Chemical Society (Resumed), 761-765.

Fairbrother, F., & Frith, W. C. (1951). 675. The halides of niobium (columbium) and tantalum. Part III. The vapour pressures of niobium (columbium) and tantalum pentafluorides. Journal of the Chemical Society (Resumed), 3051-3056.

Alexander, K. M., & Fairbrother, F. (1949). S 48. The halides of columbium (niobium) and tantalum. Part I. The vapour pressures of columbium (niobium) and tantalum pentachlorides and pentabromides. Journal of the Chemical Society (Resumed), S223-S227.