Morris has agreed a three-year-deal at Glanford Park and goes straight into the Iron squad for tomorrow night's trip to Gillingham, where he is expected to feature on the left flank.
Iron boss Brian Laws told PA Sport: "We've signed Ian as a left-sided winger and after the signing of McBreen (Daniel) as well I think we're back to where we want to be in terms of the attacking side of things.
"Ian was on loan at Blackpool last season and did well. We watched him and tried to sign him in the summer, but could not agree a fee.
"It's been on-going since then and we've managed to fend off competition from Carlisle, so credit to our chairman and the board."