The majority of doctoral researchers in Germany are financed by a position at a university - either as part of a university position with a teaching obligation or through project positions. The latter are supported by third-party funding and are not usually associated with a teaching commitment. A special form of employment increasingly exists within the framework of graduate schools or programs: here, employment is funded by third parties (e.g. the German Research Foundation) with the sole aim of writing a dissertation.

Job offers

Current job advertisements for all disciplines and qualification levels, including qualification positions (Prae-Doc) with the possibility of a doctorate, appear every Monday in the Freie Universität Berlin job advertiser.
In addition, you will find academic job offers from Freie Universität Berlin and its co-operation partners Humboldt-Universität zu Berlin, Technische Universität Berlin and Charité - Universitätsmedizin Berlin on the pages of the Berlin University Alliance.
Further job offers for doctoral researchers, can be found in the calls by the doctoral programs of the DRS and in the DRS newsletter: https://lists.fu-berlin.de/listinfo/drs-open-newsletter.

In addition to university job offers, it is also worth taking a look at non-university research institutions. Here, doctorates are awarded in co-operation with universities and excellent research conditions are offered:

Max Planck Society: https://www.mpg.de/jobboard
Leibniz Association: https://www.leibniz-gemeinschaft.de/en/careers/jobs 
Helmholtz Association: https://www.helmholtz.de/en/career/job-vacancies/
Fraunhofer Society: https://www.fraunhofer.de/en/jobs-and-career.html

On the online job portal academics.de you will find nationwide job advertisements for doctoral positions. You can sort the offers by subject area and subscribe to a weekly newsletter for your profile. You can also use the portal to search for suitable scholarships.