Abstract The paper focuses on the pad contamination defect removal technique. The defect is detected at the outgoing inspection step. The failure analysis results showed that the defect is Fluorine type contamination. The failure analysis indicated many source contributors mainly from Fluorine based processes. The focus is in the present work is in the rework method for the removal of this defect. The combination of wet and dry etch processing in the rework routine is utilized for the removal of the defect and preventive action plans for in-line were introduced and implemented to avoid this event in the future. The reliability of the wafer is verified using various tests including full map electrical, electrical sort, gate oxide breakdown (GOI) and wafer reliability level, passivation quick kill to ensure the integrity of the wafer after undergoing the rework routine. The wafer is monitored closely over a period of time to ensure it has no mushroom defect.

Abstract Heavy polymer residue has been observed on the sidewall of thick metal during the process release. The thickness of metal line is more than 3 micron. This thick polymer residue on the aluminum metal sidewall is seen from tilt Scanning Electron Microscope (SEM) profile analysis. This polymer residue on the metal sidewall with chlorine ( Cl 2) trapped will result in metal corrosion. The focus on this paper is on the removal of this polymer residue on the thick metal sidewall. The experiments were run with splits of varying the chemical dispensing time and the rinsing time in the process. The success criteria are determined by passing the Defect Source Analysis (DSA) and tilt SEM profile analysis. These wafers are sent for electrical test, wet box test (corrosion test) and electrical sort test to ensure the reliability of the post metal cleaning condition.