Dissociation of N₂ in flowing glow discharge: Influence of H₂^*

¹ Laboratório de Materiais, EMC, UFSC 88040-900-Florianópolis, SC, Brazil
² Laboratório de Materiais, EMC, UFSC 88040-900-Florianópolis, SC, Brazil CPAT, Université Paul Sabatier, 118 route de Narbonne, 31062 Toulouse Cedex, France

Received: 30 October 1997
Revised: 15 May 1998
Revised: 6 October 1998
Accepted: 6 October 1998
Published online: 15 February 1999

Abstract

The N₂ dissociation yield has been measured in a flowing post-discharge containing H₂ between 0 to 5%. The N atom density has been determined in the fast post-discharge (Δt = 5 × 10⁻² s) electric field has been measured by electrostatic probes as a function of H₂ relative concentration. It is demonstrated that the H₂ produces a significant increase in the N-atom concentration measured in the post-discharge. For our experimental conditions it was determined an increase up to 3 times in comparison to pure nitrogen discharge. The maximum yield of N-atoms was obtained for a H₂ relative concentration of about 2%. This result cannot only be explained by the decrease of N atoms surface losses. It is demonstrated that the N₂ dissociation increase is also the result of an increase of the discharge reduced electric field.