Bright metastable helium atomic beam for lithography and atom optics
K. G. H. Baldwin, Wei-Jian Lu, Dragana Milic +3 more
Intense, highly collimated sources of atoms have many potential applications. Bright beams will be important for competitive high flux and high resolution direct-write techniques in lithography, with the added advantage of parallel writing through laser manipulation. Intense sources will also be useful in other atom optic devices e.g. for loading atoms into hollow fiber waveguides. In atomic physics, many collision processes can only be measured with the sensitivity offered by such high flux sources. We report progress on the development of an intense, collimated beam of metastable helium atoms which improves the brightness generated by conventional nozzle discharge sources by several orders of magnitude. The system uses diode lasers to transversely collimate and then to longitudinally slow the atoms, using Zeeman tuning to compensate for the changing Doppler shift. The slowed, collimated beam is then compressed in a 2D magneto-optic trap before a final collimation stage, to achieve the required increase in intensity. Initial experiments using the helium source for some of the applications above are described.
Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•May 1, 1997•4 citations