Semiconductor structure

Abstract

A semiconductor structure includes a semiconductor device, a conductive line, a dielectric layer and a redistribution layer (RDL). The conductive line is present over the semiconductor device. The dielectric layer is present over the conductive line. The RDL includes a conductive structure over the dielectric layer and a conductive via extending downwards from the conductive structure and through the dielectric layer. The conductive via comprises a bottom portion, a top portion, and a tapered portion between the bottom and top portions, wherein the tapered portion has a width variation greater than that of the bottom and top portions.

What is claimed is: 
     
         1 . A semiconductor structure, comprising:
 a semiconductor device;   a conductive line over the semiconductor device;   a dielectric layer over the conductive line; and   a redistribution layer (RDL) comprising a conductive structure over the dielectric layer and a conductive via extending downwards from the conductive structure and through the dielectric layer, wherein the conductive via comprises a bottom portion, a top portion, and a tapered portion between the bottom and top portions, wherein the tapered portion has a width variation greater than that of the bottom and top portions.   
     
     
         2 . The semiconductor structure of  claim 1 , wherein the tapered portion tapers from the top portion to the bottom portion. 
     
     
         3 . The semiconductor structure of  claim 1 , wherein the bottom portion is in contact with the conductive line. 
     
     
         4 . The semiconductor structure of  claim 1 , further comprising:
 a protective layer over the RDL.   
     
     
         5 . The semiconductor structure of  claim 1 , wherein a bottom surface of the conductive via is below a top surface of the conductive line.