Hi
Special characters might help but phaffy and it depends on the font used.
Probably the simplest way is to use two text boxes on different tracks one above the other; one for the actual text numbers and the other for the superscript....
Use a Position effect to move the superscript character (with a smaller font size) to a slightly higher position than the main text. Use a separate text image for each different superscript character you are going to use.
Nat