Matchbox 20 was on my radio with “Real World” today, and I was reminded that we must add this to the list of 90s songs with Superman references (though this reference is indirect):
Wasn’t there a band from the late 1800’s called The Nietzsches that wrote something about Superman?
I actually saw It’s a Bird, It’s a Plane, It’s Superman on Broadway. 
If we’re expanding our horizons to other superheroes, there is Scaffold’s “Goodbat Nightman” from 1966, the only rock song to have its lyrics reprinted in the Oxford Book of Modern English Verse.
You may be thinking of the singing duo, Falco and Nena, who did Übermensch in German. It was After the Incandescent Bulb who did the English-language version.