Inter's 2-2 draw with Bayern Munich last night saw the Nerazzurri reach the final four 4-3 on aggregate.
Sommer, a former Bayern keeper, said afterwards: "I'm very tired and very happy, we played a good game against a very strong opponent. In the second half we defended as a team, I'm very happy."
On Bayern's full assault in the final ten minutes, Sommer said: "It's always like this, even in Munich.
"I know Bayern very well, the pressure they put on is tough and we did well. We were too low, but we all defended: that's how we win games."
On what reaching the semis means for the club, he also stated: "Let's see, this is the objective. However, we saw today that you really have to give your all to stay at a high level.
"Now we are happy, we won against the favourites this season to win the Champions League."