Dielectric slots underneath conductive vias in interconnect structure of semiconductor package and method of forming the same

Abstract

A method of manufacturing a semiconductor package includes depositing a first dielectric layer over a carrier substrate. A first metallization pattern is formed over the first dielectric layer. The first metallization pattern has a first opening exposing the first dielectric layer. A second dielectric layer is deposited over the first metallization pattern, forming a dielectric slot through the first metallization pattern by filling the first opening. A second metallization pattern and a third dielectric layer are formed over the second dielectric layer. A through via is formed over the third dielectric layer, so that the dielectric slot is laterally under the through via.