A method of forming a bump overlying the copper based contact pad to prevent oxidation of the copper based contact pad. A passivation blanket is deposited over a semiconductor device having a copper based contact pad, the passivation blanket includes a first layer overlying the top surface; a second layer overlying the first layer; a portion of the second layer overlying the copper based contact pad is removed leaving the first layer in place; depositing an under bump metallurgy over the semiconductor device, a portion of the first layer overlying the copper based contact pad is removed so that the copper based contact pad has limited exposure to oxygen; depositing an under bump metallurgy over the semiconductor device; removing excess under bump metallurgy; depositing an electrically conductive material over the under bump metallurgy; reflowing electrically conductive material to form a bump overlying the copper based contact pad.