Robert Weiss1, *Alexander Welsh1, Nicholas White2
1Malachite Technologies, San Francisco, CA; 2Albion Systems, Manchester, MA
We present source design and process results of a uniquely scalable ribbon ion beam source for modifying glass surfaces to reduce reflectance. One of the compelling needs for anti-reflective glass comes from the solar power industry. Energy yields from solar modules directly benefit from reduced glass reflectance. A variety of additive processes – sputtered films, solution-based films, particle-based layers – have been developed and commercialized to serve the PV industry but the relatively high cost per added watt of output has limited the product introductions. Along with the cost challenge, additive films struggle to match the lifetime of the module. Surface modification of glass for reduced reflectance by ion implantation was first reported in the early 1980s. Modifying the surface, rather than adding a layer onto the surface, has the advantage of providing long-lived results. Cost for ion implantation equipment has severely limited the technique’s utility for large area applications. Our ion source, currently under development, generates a ribbon beam, scalable to over 2 meters length with ion currents of up to one amp per linear meter using a 3 mm width single slit extraction. The three-electrode extraction system provides beam energies up to 50 keV. Beam divergence can be as low as +/-2 degrees even without beam neutralization.