Naomh Conaill beat St Eunan's 0-11 to 0-10 in the Donegal club decider despite playing the last 20 minutes with 14 men at Ballybofey.
St Eunan's led by a point at the break but Naomh Conaill fought back to win after Eoghan McGettigan's red card.
Cargin defeated Lamh Dhearg 2-11 to 1-5 in the Antrim final at Ahoghill to set up an Ulster quarter-final meeting against Armagh champions Crossmaglen.
Scotstown overcame Monaghan Harps 2-12 to 0-9 in the Farney final at Clones.
Early goals from Orin Heaphey and Conor McCarthy set Scotstown on their way to comfortable victory on Sunday.
Harps were seeking a first county success since 1923 but they struggled to keep in touch with Scotstown and they had Neil McAdam red-carded in stoppage time.
Scotstown now face a tough Ulster quarter-final clash against holders Slaughtneil, who eased past Derrygonnelly in Sunday's preliminary round tie.
What they said
Scotstown player Kieran Hughes: "It is pure relief to come through in the final and we can now look forward to the Ulster championship.
"We will enjoy this victory but from Tuesday we have to get focused again and we are under no illusions about how tough a game it will be against Slaughtneil.
"At the minute I'm just a very, very happy man to be playing in the Ulster club championship."