No tax is paid. Will not entitle you to a pension. The same for everybody, not negotiable. Tax is paid. Will entitle you to a pension.
Tax is paid.
Will entitle you to a pension. Half-time control does not automatically entitle to a pay raise since it's not an academical degree. However , remember that you're only supposed to have the minimal salary if you're completely new at the department, have no experience, and don't teach. If you've done your half-time control, you're more than half way through your education and should not have minimal salaries.