System and method for forming serial numbers on HDD wafers
View Patent ↗Both the wafer serial number and slider region location indicia on the wafer are formed on the front surface of the wafer using optical principles, i.e., without using a laser.
1. A wafer comprising:
a wafer body having a plurality of devices formed upon the wafer, wherein each of said devices has a unique serialization number associated with it and wherein the serialization number is not adjacent to the wafer back surface, the wafer including a wafer number including alphanumeric characters at least a first one of which corresponds to a specific reticle and location on that reticle, such that the reticle, location on the reticle for the first alphanumeric character, and the location of the first alphanumeric character on the wafer determine a stepper job from a plurality of jobs.
2. A wafer, comprising:
a front surface and an opposed back surface;
indicia on the front surface representing a location on the wafer of each of plural slider regions;
at least one serial number on the front surface representing the wafer itself; and
a material which is transparent to a reading device that is to be used to read the indicia encapsulating the indicia such that no unfilled cavities are associated with the indicia to trap contaminants on the wafer.