Patent Number: 
Section: claims

1. A target unit for producing Cu67 radioisotope comprising:a cage body releasably coupled to a screw-on cap; anda ceramic capsule containing a solid Zn68 target ingot and having one open end and one closed end and defining an interior chamber for the target ingot;wherein the ceramic capsule is releasably contained between the cage body and the screw-on cap with a lid disposed on the open end of the capsule and a washer positioned between the lid and the screw-on cap, wherein the screw-on cap and the washer provide a water-tight seal between the lid and the capsule; the interior of the ceramic capsule is in intimate physical contact with the solid Zn68 target ingot; and the Zn68 of the target ingot is free of traces of residual oxygen that interfere with contact of the Zn68 to the capsule. 2. The target unit of claim 1, wherein the cage body and the screw-on cap are composed of aluminum. 3. The target unit of claim 1, wherein the cage body and the screw-on cap are composed of different alloys of aluminum to minimize the possibility of thread galling. 4. The target unit of claim 1, wherein the cage body and the screw-on cap are each composed of different alloys of aluminum selected from the group consisting of 6061 Al and 2024 Al. 5. The target unit of claim 1, wherein the cage body includes apertures to allow cooling water to contact the capsule during irradiation thereof to prevent melting or partial melting of the zinc target ingot during the irradiation. 6. The target unit of claim 1, wherein the ceramic capsule is composed of a material selected from the group consisting of alumina and aluminum nitride. 7. The target unit of claim 1, wherein the capsule is composed of alumina. 8. A target unit for producing Cu67 radioisotope comprising:a cylindrical cage body with a threaded open end;a screw-on cap threaded to mate with the threaded open end of the cage body;a ceramic capsule having one open end and one closed end, and defining an interior chamber containing a Zn68 target ingot in intimate physical contact with the capsule;a removable lid covering the open end of the capsule; anda gasket disposed between the open end of the capsule and the lid;wherein the ceramic capsule, the lid, and the gasket are arranged within the interior cavity of the cage body with the lid in contact with the screw-on cap when the cage body is mated with the screw-on cap, so that the screw-on cap applies a pressure on the lid and gasket sufficient to form a water-tight seal over the open end of the capsule when the unit is fully assembled for use; and the Zn68 of the target ingot is free of traces of residual oxygen that interfere with contact of the Zn68 to the capsule. 9. The target unit of claim 8, wherein the cage body and the screw-on cap are composed of aluminum. 10. The target unit of claim 8, wherein the cage body and the screw-on cap are composed of different alloys of aluminum to minimize the possibility of thread galling. 11. The target unit of claim 8, wherein the cage body and the screw-on cap are each composed of different alloys of aluminum selected from the group consisting of 6061 Al and 2024 Al. 12. The target unit of claim 8, wherein the cage body includes apertures to allow cooling water to contact the capsule during irradiation thereof to prevent melting or partial melting of the zinc target ingot during the irradiation. 13. The target unit of claim 8, wherein the ceramic capsule is composed of a material selected from the group consisting of alumina and aluminum nitride. 14. The target unit of claim 8, wherein the capsule is composed of alumina. 15. The target unit of claim 8 wherein the gasket is composed of graphite.