Patent ID: 6881675

Claim:
A method for reducing wafer edge residue following a chemical mechanical polishing operation, said method comprising the steps of: polishing a semiconductor wafer utilizing a chemical mechanical polishing apparatus, wherein chemical mechanical polishing thereof can result in a poor adhesion between at least one IMD layer and a passivation film formed upon said semiconductor wafer; thereafter performing an acid etch operation to remove a residue collected on said semiconductor wafer as a result of said chemical mechanical polishing operation; delivering an N 2 gas flow to said semiconductor wafer using a first nozzle to produce a non-contact interface between said semiconductor wafer and a chuck, thereby preventing said poor adhesion between said at least one IMD layer said passivation film resulting from said chemical mechanical polishing and avoiding follow-up polymide peeling caused by thermal stresses resulting from alloy and curing of said semiconductor wafer; and delivering an N 2 gas flow adjacent to said semiconductor wafer using a second nozzle to prevent residue acid vapor from back-diffusion.