Growth of fluorocarbon macromolecules in a gas phase (I). Mass spectrometric investigation of products in the downstream region of Ar/CF ₄ plasmas

The growth of gaseous neutral species and positive ions was investigated in the downstream region of Ar/CF₄ plasmas by mass spectrometry. As a result, there were several series of C_nF_2n+1⁺ (n = 1-7), C_nF_2n-1⁺ (n = 3-8) and C _nF_2n-3⁺ (n = 4-9) for the positive ions and C_nF_2n+2 (n = 2-7) and C_nF_2n (n = 4-8) for the neutral species. The intensity dependence of the positive ions on the partial pressure of CF₄ was quite different from that of the neutral species, demonstrating that their growth mechanisms are independent of each other.