CAD tip # 5544:

Choose one of the fonts supporting full Unicode (e.g Arial Unicode MS) and write the super/subscript text using special characters. You can enter the Unicode character using its code \U+nnnn (in AutoCAD), by mapping it to a keyboard key or by copying it from the application "Character Map" (charmap.exe).

Superscripts:

  
0 - U+2070  
1 - U+00B9  
2 - U+00B2  
3 - U+00B3  
4 - U+2074  
5 - U+2075  
6 - U+2076  
7 - U+2077  
8 - U+2078  
9 - U+2079  
+ - U+207A  
- - U+207B  
( - U+207D  
) - U+207E  
n - U+207F  

  
0 - U+2080  
1 - U+2081  
2 - U+2082  
3 - U+2083  
4 - U+2084  
5 - U+2085  
6 - U+2086  
7 - U+2087  
8 - U+2088  
9 - U+2089  
+ - U+208A  
- - U+208B  
( - U+208D  
) - U+208E