Semiconductor device and method of wafer thinning involving edge trimming and cmp

Abstract

A semiconductor device has a substrate including a plurality of conductive vias formed vertically and partially through the substrate. An encapsulant is deposited over a first surface of the substrate and around a peripheral region of the substrate. A portion of the encapsulant around the peripheral region is removed by a cutting or laser operation to form a notch extending laterally through the encapsulant to a second surface of the substrate opposite the first surface of the substrate. A first portion of the substrate outside the notch is removed by chemical mechanical polishing to expose the conductive vias. A second portion of the substrate is removed by backgrinding prior to or after forming the notch. The encapsulant is coplanar with the substrate after revealing the conductive vias. The absence of an encapsulant/base material interface and coplanarity of the molded substrate results in less over-etching or under-etching and fewer defects.