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The MAJORANA DEMONSTRATOR is an array of point-contact Ge detectorsfabricated from Ge isotopically enriched to 88% in Ge-76 to search forneutrinoless double beta decay. The processing of Ge for germanium detectors isa well-known technology. However, because of the high cost of Ge enriched inGe-76, special procedures were required to maximize the yield of detector massand to minimize exposure to cosmic rays. These procedures include carefulaccounting for the material; shielding it to reduce cosmogenic generation ofradioactive isotopes; and development of special reprocessing techniques forcontaminated solid germanium, shavings, grindings, acid etchant and cuttingfluids from detector fabrication. Processing procedures were developed thatresulted in a total yield in detector mass of 70%. However, none of theacid-etch solution and only 50% of the cutting fluids from detector fabricationwere reprocessed. Had they been processed, the projections for the recoveryyield would be between 80 -- 85%. Maximizing yield is critical to justify apossible future ton-scale experiment. A process for recovery of germanium fromthe acid-etch solution was developed with yield of about 90%. All material wasshielded or stored underground whenever possible to minimize the formation ofGe-68 by cosmic rays, which contributes background in the double-beta decayregion of interest and cannot be removed by zone refinement and crystal growth.Formation of Ge-68 was reduced by a significant factor over that in naturalabundance detectors not protected from cosmic rays.

The Processing of Enriched Germanium for the MAJORANA DEMONSTRATOR and R&D for a Possible Future Ton-Scale Ge-76 Double-Beta Decay Experiment