Analysis of Electron Transport Coefficients in SiH4 Gas Using Boltzmann Equation in the Presence of Applied Electric Field

  • Mohammad M. Othman Department of Physics, College of Education,Salahaddin University-Erbil, Kurdistan Region, Iraq
  • Sherzad Aziz Taha Physics Department Education College,Salahaddin University-Erbil, Kurdistan Region, Iraq
  • Idrees Hadi Salih Tishk International University, Erbil, Kurdistan Region, Iraq
Keywords: Swarm parameters EEDF Effective ionization coefficient. Plasmas Boltzmann equation


Monosilane (SiH4) plasma has numerous applications in plasma processing, transport coefficients   are better to understanding and modeling of these gas discharge processes. The electron swarms in a monosilane gas under influence of uniform electric field can be calculated using two term approximation of Boltzmann equation for the range 1 ≤ E/N ≤ 1000 Td (1 Td= 1x10-17 V.cm2). The effective ionization coefficient's (α-η)/N and electron swarm parameters are calculated and compared with experimental and theoretical values  of drift velocity, characteristic energy, mean electron energy and ionization coefficient. The critical field strength (E/N) calculated from the effective ionization curves. A set of electron molecule collisions has been assembled for monsilane gas which gave a good fit between the calculated and experimental values over the range of  E/N investigated. The calculated distribution functions (EEDF) are found to be non-Maxwellian, having energy variations which reflect the important electron / molecule energy exchange processes. In addition, the percentages of energy lost by different types of elastic and inelastic collisions are given as a function of  electric field strength E/N.

Author Biography

Sherzad Aziz Taha, Physics Department Education College,Salahaddin University-Erbil, Kurdistan Region, Iraq

PhD in Ionization in solid material 

Moleculaer and atomic interaction with matter


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How to Cite
Othman, M., S. Taha, and I. Salih. “Analysis of Electron Transport Coefficients in SiH4 Gas Using Boltzmann Equation in the Presence of Applied Electric Field”. ZANCO Journal of Pure and Applied Sciences, Vol. 31, no. 1, Feb. 2019, pp. 77-88, doi:10.21271/zjpas.31.1.10.