Review on vacuum ultraviolet generation in low-pressure plasmas

Low-pressure nonequilibrium plasmas can be a source of intense radiation in the vacuum ultraviolet (VUV) range which can play an important role in the surface modification of solid materials. Herein, we review the available literature on VUV radiation from low-pressure gaseous plasmas sustained by inductively and capacitively coupled radiofrequency discharges, microwave, and magnetized discharges. The reported VUV fluxes range from about 10(14)-10(17) photons cm(-2)center dot s(-1) while electron density range from 10(9) to 10(12) cm(-3). The correlations between the measured VUV fluxes and parameters, such as gas pressure, electron density, and discharge power are shown. The results summarized in this study represent a rough guide for the scientists involved in plasma-surface interactions. As the flux of VUV photons depends on numerous parameters, it is currently only possible to estimate its order of magnitude.