Germanium Isotopes are mainly used for the production of medical As and Se radioisotopes. Ge-74 is used for the production of As-74, Ge-76 for the production of As-77, Ge-74 for the production of As-73 and Ge-72 for As-72. Ge-70, Ge-72 and Ge-74 can all be used for the production of the medical radioisotope Se-73, although the most common production route is via natural As (As-75). Natural GeF₄ is used in the semiconductor pre-amorphisation implant process. The use of Ge-72, in the form of GeF₄, improves this process and reduces contamination. Finally, Ge-76 is used to study double beta decay.