Jonas Hector hit the crucial German penalty to seal the world champions' 6-5 victory in Bordeaux to claim an historic win over Italy.
It was the first time Germany have beaten the Azzurri in nine attempts at a World Cup or European Championships finals.
"From a fighter's point of view, it was amazing what the side did," said Loew as Germany reached the semis at a Euro finals for the third time in a row.