A high-frequency UV-VUV radiation source operating on a mixture of argon with chlorine molecules

Abstract

We present the working optical characteristics of a short-wavelength electric-discharge lamp operating at 150–270 nm (UV-VUV spectral range). The working medium is a mixture of argon with chlorine molecules (Ar-Cl2) excited in a high-frequency transverse discharge between a metal electrode and a semitransparent nickel grid with an interelectrode distance of 2.2 cm. The proposed UV-VUV radiation source operates on the broadened emission lines of chlorine (Cl2) and argon chloride (ArCl) molecules, which form a continuum in the 150–270 nm wavelength range. The source operation was optimized depending on the pumping power and the pressure and composition of the Ar-Cl2 mixture. For a discharge excitation power within 50–300 W, the optimum working media were Ar-Cl2 mixtures with the partial pressures P(Ar) = 300−400 Pa and P(Cl2) = 30−40 Pa. The average total output power of the UV-VUV radiation extracted from the optimized source amounted to 15 W.