After having received your master's degree, you might consider continuing your academic studies by doing a doctoral program.
Please bear in mind that the scope of a doctoral or PhD thesis differs considerably from that of a master's thesis. The WU offers more information on its doctoral studies here. The minimum duration of the doctoral program is six semesters. However, IIB students usually require longer. Note also that most candidates are employed as research and teaching assistants at the institute.
For current job openings as a teaching and research associate, visit WU’s jobs page.