Electron-beam–ignited, high-frequency–driven vacuum ultraviolet excimer light source

Transformation of a table-top electron-beam–sustained 2.45 GHz RF discharge in rare gases into a self-burning discharge has been observed for increasing RF amplitude. Thereby, the emission spectrum undergoes significant changes in a wide spectral range from the vacuum ultraviolet (VUV) to the near infrared. A strong increase of VUV excimer emission is observed for the self-burning discharge. The so-called first excimer continuum, in particular, shows a drastic increase in intensity. For argon this effect results in a brilliant light source emitting near the 105 nm short-wavelength cutoff of LiF windows. The appearance of a broad-band continuum in the UV and visible range as well as effects of RF excitation on the atomic line radiation and the so-called third excimer continuum are briefly described.