I tried tape, and it works, but it eventually starts coming off.
I ended up going with a teflon-based lubricant in that corner. I apply a very thin dab and smear it lightly with my finger and the creak is gone.
I have to reapply about every 2 weeks or so.
no damage to the phone
hasnt attracted any dirt or debris, and its alot easier to do than cutting and applying tiny pieces of tape.
works for me