摘要
Using a combination of the Monte Carlo models of fast electrons, of molecular ions (N+) and of atomic species (N^+, Nf), the influence of the discharge pressure (P) and voltage (Vc) on the energy distributions of fast atomic species (N^+, Nf) produced by e^--N2s and N2^+- N2s dissociation reactions at the cathode in a nitrogen dc glow discharge was investigated. Both the angular distributions and the density distributions along the radius of the species (N^+, Nf) produced by the two dissociations at the cathode were calculated. The results show that: (1) there is an optimum discharge condition for P and Vc in order to obtain the species (N^+, Nf) at the cathode with high a density and energy, (2) when the voltage is above 800 V, the species (N^+, Nf) bombarding the cathode are mainly produced by the N^+-N2s dissociation, whereas when the voltage is below 300 V, they are mainly produced by the e-N2s dissociation, and (3) at high Voltages the incident angles of a considerable number of Nf into the cathode are quite small. The density of the species (N^+ Nf) at the cathode increases with the voltage, and when the pressure goes up to about 133 Pa, it decreases with the increasing pressure.
Using a combination of the Monte Carlo models of fast electrons, of molecular ions (N+) and of atomic species (N^+, Nf), the influence of the discharge pressure (P) and voltage (Vc) on the energy distributions of fast atomic species (N^+, Nf) produced by e^--N2s and N2^+- N2s dissociation reactions at the cathode in a nitrogen dc glow discharge was investigated. Both the angular distributions and the density distributions along the radius of the species (N^+, Nf) produced by the two dissociations at the cathode were calculated. The results show that: (1) there is an optimum discharge condition for P and Vc in order to obtain the species (N^+, Nf) at the cathode with high a density and energy, (2) when the voltage is above 800 V, the species (N^+, Nf) bombarding the cathode are mainly produced by the N^+-N2s dissociation, whereas when the voltage is below 300 V, they are mainly produced by the e-N2s dissociation, and (3) at high Voltages the incident angles of a considerable number of Nf into the cathode are quite small. The density of the species (N^+ Nf) at the cathode increases with the voltage, and when the pressure goes up to about 133 Pa, it decreases with the increasing pressure.
基金
supported by the Natural Science Foundation of Hebei Province,China(No.A2006000123)