Taiwanese visiting the Schengen area without a visa will also need to make sure that they meet the entry requirements as laid down in the Schengen Borders Code:
possess a valid Taiwanese passport including an ID-number on the datapage satisfying the following criteria
- its validity shall extend at least three months after the intended date of departure from the territory of the Schengen Member States;
- it shall have been issued within the previous 10 years
justify the purpose of his/her intended stay and have sufficient means of subsistence
not have an alert issued for him/her in the Schengen Information System for the purpose of refusing entry
not be considered a threat to public policy, internal security, public health or the international relations of EU countries etc.
Once you have made use of your maximum length of stay (90 days per six months) in the Schengen area, you have to wait until the relevant period of six months has run out, before travelling to Germany or another Schengen State again. The six month period starts from the day on which you first entered Germany or another Schengen-Member State.