An apparatus and method for preventing the peeling of electroplated metal
from a wafer, is disclosed. The apparatus includes a seed layer detector
system having a light source and a reflectivity detector. According to
the method, the light source emits a beam of light onto a wafer and the
reflectivity detector receives the light reflected from the wafer. The
reflectivity of the wafer surface is measured to determine the presence
or absence of a seed layer on the wafer, as well as whether the seed
layer has a minimum thickness for optimum electroplating of a metal onto
the seed layer.