A detailed comparison of spectral line intensities with plane and hollow cathodes in a Grimm type glow discharge source

Abstract

The hollow cathode discharge was investigated and compared with the plane cathode discharge in a Grimm-type source studying a large number of lines with iron and titanium as cathode materials in argon plasma. The high resolution Fourier Transform Spectrometer (FTS) at Imperial College (IC) was used for recording spectra. The intensity changes for atomic and ionic lines of iron, titanium and argon are discussed, whereby clear trends in intensity increase and reduction according to the excitation energies of the emission lines are identified. Differences in line profiles in spectra using the hollow and plane cathodes were detected. The comparison between the hollow (10–15 mm deep) and shallow (2 mm deep) cathodes gives additional information about the depth influence on the hollow cathode effect. The extended study presented in this paper is a further step towards a better understanding of the discharge processes in the glow discharge.