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Database of the Thermophysical Properties of Gases Used in the Semiconductor Industry

The 1999 Semiconductor Industry Association (SIA) International Technology Roadmap for Semiconductors (ITRS) identifies "Equipment Modeling" as first in a list of "Technology Requirements" and states that "the drivers for equipment modeling are equipment design, process control, . . . " The ITRS indicates that continuing research is needed to obtain experimental data for "transport and thermal constants." This Project will generate transport and thermodynamic property data for the gases used in semiconductor processing. The data will be useful for equipment modeling in chemical vapor deposition (CVD) processes and the data will also provide a rational basis for the calibration of mass flow controllers (MFCs) used to meter process gases.

NIST is measuring the thermophysical properties of the process gases, the "surrogate" gases, and binary mixtures of process and carrier gases. The process gases are used in CVD and the surrogate gases are used to calibrate MFCs. The results will be disseminated in this data base providing the heat capacity, thermal conductivity, viscosity, and the virial coefficients for the virial equation of state providing the pressure-density-temperature relation for the process gases.


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  2. Horvath, A.L., "Physical Properties of Inorganic Compounds," Crane Russak, New York, 1975
  3. IUPAC, "Atomic Weights of the Elements 1993," J. Phys. Chem. Ref. Data (1995, 24, 1561)
  4. Verdelli, L.S., Miller, H.C., Gall, J.F., "Some Physical Properties of Sulfur Hexafluoride," Ind. Eng. Chem. (1951, 43, 1126).
  5. Hurly, J.J., Defibaugh, D.R., and Moldover, M.R., "Thermodynamic Properties of Sulfur Hexafluoride," Int. J. Thermophysics v21, 739 (2000).

Formerly known as SRD 134, but reclassified as a data compilation to be consistent with the Standard Reference Data Act of 1968 and, as amended, January 2017.


General Information

Created December 1, 2009, Updated June 2, 2021