Patent ID: 9196532
Filing Date: 2015-11-24
Classification: H01L

Abstract:
1. A method comprising: forming an electrical connector over a substrate of a wafer, wherein the electrical connector comprises a solder ball; dispensing a liquid molding compound, wherein a lower portion of the solder ball is in the liquid molding compound, and wherein an upper portion of the solder ball is above a top surface of the liquid molding compound; curing the liquid molding compound to form a polymer layer; performing a first sawing step to form a trench in the polymer layer, wherein after the first sawing step, a remaining portion of the polymer layer is left underlying the trench, wherein the remaining portion of the polymer layer has a thickness allowing a feature underlying the polymer layer to be visible through the remaining portion; and after the first sawing step, performing a second sawing step to saw the wafer into a plurality of dies, wherein during the second sawing step, the feature is used as an alignment mark.