Metal pad of semiconductor device

Metal pads of semiconductor device are located in the opening of the passivation layer and are connected to the metal connection layer of the semiconductor devices through plural metal plugs. They consist of a first aluminum alloy layer, a laser stop layer and a second aluminum alloy layer. The said first aluminum alloy layer is located upon the metal plugs; the said laser stop layer is located on the first aluminum alloy layer and is composed of metal having high melting point and high laser reflectance. The thickness of the laser stop layer is between 500 to 5000 angstroms. The said second aluminum alloy layer is located upon the laser stop layer and its thickness is between 1000 to 20000 angstroms.