High-performance beamline for vacuum-ultraviolet-excited material processing

A high-performance beamline dedicated to vacuum-ultraviolet (VUV)-excited semiconductor processing has been constructed on the compact electron storage ring "Super ALIS". The first toroidal mirror accepts photons (emitted at a bending magnet) for 70 mad in the horizontal direction, and the reflected parallel beam is focused onto the specimen surface by the second toroidal mirror. A brilliant VUV beam (with a photon density of 1.3 x 10(16) s(-1) mm(-2) when the ring current is 300 mA) illuminates a circular field (10 mm in diameter) on the target surface. The eight 5-m-long differential pumping stages allow the reactant gas to be introduced into the reaction chamber at pressures up to 0.1 Torr. The processing is monitored in real time by using ultraviolet phase-modulated spectroscopic ellipsometry, and VUV-stimulated evaporation of SiO2 film has been demonstrated. (C) 1998 American Institute of Physics.