BAT and TVÖD Salary Scale for Doctoral Sudents in Germany

Most doctoral student positions in Germany are advertised as TV-L 13,
or sometimes still as BAT IIa or BAT IIa/2. What is that? Here's a
quick reference:
http://www.cats.rwth-aachen.de/jobs/bat

General

TV (or TVÖD) stands for Tarifvertrag im Öffentlichen Dienst while BAT
stands for Bundesangestelltentarif. Both mean tariffs for German civil
service employees. The TV tariffs determine the salary based on
experience and family situation; the older BAT tariffs depend on age as
well as family situation; there is normally no variability based on
negotiation or location. These tariffs are periodically adjusted for
inflation. In the former East Germany, they are set a bit lower than in
the former West, but this difference is decreasing and will eventually
disappear.

TV-L 13

TV level 13 is the tariff that doctoral students in engineering,
computer science and applied math (high-demand occupations) qualify
for. For a single person this means a gross salary of about €2800 per
month and about €3100 after one year. Compared to most doctoral
stipends in the US, this is a fantastic deal. Working hours are 39.83
per week. That's 10 minutes and 12 seconds less than 40—talk about
German precision! Paid vacation is, depending on age, between 26 and 30
days per year, if that's what you're into.

BAT IIa

This tariff was replaced by TV-L 13 in late 2006.

BAT IIa/2

Doctoral students in other fields—pure mathematics, natural sciences,
humanities—get half of the BAT IIa salary for the same amount of work.

Stipend

Some doctoral positions involve stipends rather than salaries; these
are typically part of research training group (Graduiertenkolleg or
GRK), i.e., a group of doctoral students working on a single theme.
These range between €1100 (standard) and €1500 (augmented, or erhöhtes
Stipendium). The advantage of these positions is a structured doctoral
program that leads to a doctorate in about 3 years after M.S. Some
program like the AICES graduate school offer stipends of €2000, which
is more competitive with the TV-L 13 scale, while offering the benefits
of a structured doctoral program.

Postdoc

Postdocs are often paid on the same pay scale as the doctoral students,
i.e., TV-L 13 or BAT IIa. By virtue of being older and having more
experience, that may mean higher salary though. Also, postdoctoral
positions with special responsibilities, such as junior research group
leaders, may carry higher salary category, e.g., TV-L 14 (formerly BAT
Ib) or TV-L 15 (formerly BAT Ia), or even the highest TV-L 15Ü
(formerly BAT I). Working hours remain, alas, at the magic 39.83 hours
per week.

Average salaries (including benefits) are also listed in a German (attached in PDF).