IPC-4556-AM1 is the amendment 1 to the standard IPC-4556 and made the following changes to the base specification: a) It added the absolute value of the maximum thickness for the immersion gold of 0.070 μm [2.8 μin] that accompanies the statistically valid minimum immersion gold thickness; b) It added two more photomicrograph images to provide better information on identifying nickel hyper...