Joint Russian and Bulgarian Academies of Sciences Database of Intermolecular Potentials and Diffusion Coefficients for Components of the CVD Processes in Microelectronics

Abstract

The goal of the database (DB) EPIDIF-JRB is to promote the modeling of gas-phase transport processes in CVD technologies in microelectronics. The transport properties (molecular diffusion coefficients, viscosity, and thermal conductivity) of pure gases and gas mixtures in the temperature range 250 to 2000K and at a pressure <0.1MPa are calculated using (1) the Chapman–Enskog method in binary collision approximation and (2) the three-parameter Lennard–Jones (m–6) intermolecular potentials (IP) with 8<m<100 for interactions of atoms and quasi-spherical molecules, and (3) the four-parameter m–6–3 Stockmayer IP for dipole molecules. In addition to the IP parameters aii, ajj, and aij, the DB also supplies their variance–covariance matrix. For heavy globular molecules [such as CF4, SiH4, Si(CH3)4, and WF6], the influence of the vibrational excitation on their effective size is considered. In this case, the isotropic Lennard–Jones (m–6) IP with temperature-dependent parameters was defined. At present, the DB EPIDIF-JRB contains 40 species of importance to Si gas-phase epitaxy processes and IP parameters for 820 pair interactions. It can be used to calculate the viscosity of pure gases and gas mixtures with any k components (k<11), and their binary diffusion coefficients, and to estimate their uncertainty as well.