Patent ID: 8282846

Claim:
A method for preventing metal corrosion on a bond pad of an integrated circuit device, the method comprising the steps of: applying an anti-reflective coating layer to the bond pad; depositing a passivation layer over the anti-reflective coating layer and etching an aperture through the passivation layer and the anti-reflective coating layers down to the bond pad, the anti-reflective coating layer aperture having an upper edge, a lower edge, and a sidewall surface extending between the upper edge and the lower edge, the sidewall surface formed during formation of the anti-reflective coating layer aperture and the passivation layer aperture having an upper edge, a lower edge, and a sidewall surface extending between the upper edge and the lower edge, the sidewall surface formed during formation of the passivation layer coating layer aperture; depositing a conformal protective layer to touch the top surface of the passivation layer and line the aperture opening to touch the side wall of the passivation layer, the side wall of the anti-reflective layer and the top surface of the bond pad; and anisotropically etching the conformal protective layer until the center region of the bond pad is exposed, wherein the etching leaves a protective sidewall spacer that covers (i) the sidewall surface of the anti-reflective coating layer aperture, (ii) the sidewall surface of the of the passivation coating layer and (iii) a portion of the bond pad, wherein the side wall spacer has a lower width that is substantially larger than an upper width.