[9p-M113-1~8] 6.2 Carbon-based thin films

[9p-M113-5] Dissociative excitation process of C₂H₂ by the microwave discharge flow of Ar: Mechanism of dissociation via the superexcited state

〇Haruhiko Ito¹, Hiroki Tsudome¹ (1.Nagaoka Univ. of Tech.)

Keywords:Plasma CVD, Dissociation mechanism of acetylene

In the dissociative excitation reaction of acetylene with the microwave discharge flow of Ar, the strong emission spectrum corresponding to the CH(A-X) transition can be observed. In this study, the mechanism of the production of the CH(A) state is discussed. From the experiments, it is concluded that the CH(A) state is formed from the charge transfer from Ar⁺ followed by the recombination of free electrons. According to the reported absorption spectrum of acetylene in the vacuum ultraviolet region, the existance of the superexcited state is suggested. This state is either autoionized or dissociated into CH(A) state. From the above considerations, it is concluded that the ion-elenctron recombination may form the sperexcited state followed by the dissociation into the CH(A) state.