The 25-year-old, who won bronze at the 2012 Olympics, was keen to get his professional career off on the right foot after the disappointment of the Rio Games.
Conlan’s first professional fight was in front of a packed house at New York’s Madison Square Garden and he put on an entertaining performance for the 5,000 travelling Irish fans.
The highly-rated Belfast man forced referee Benjy Esteves Jr to step in and stop the bout after a powerful right hand put Ibarra on the ropes.
The former world amateur champion admitted he was worried about putting in a good performance and feels he still has plenty of room for improvement.
Conlan said: "There was pressure and the thing I was most worried about was my performance.
"At times it showed because I was a bit reckless and was not timing my shots. I was just looking for the knockout.
"I am grateful to all the fans who travelled here. I have never experienced anything like that atmosphere in my life.
"To have that on my debut - I do not think it will ever be beaten."