Manufacturing method of die-stack structure

Abstract

The present disclosure provides a manufacturing method of a die-stack structure including follow steps. A first wafer including a first die is provided, wherein the first die includes a first substrate material layer, a first interconnect structure, and a first pad, and the first interconnect structure and the first pad are formed on the first substrate material layer in order, and the first substrate material layer has a first contact conductor disposed therein. The first contact conductor is disposed in the first substrate material layer. A second wafer including a second die is provided, wherein the second die includes a second substrate material layer, a second interconnect structure, and a second pad, and the second interconnect structure and the second pad are formed on the second substrate material layer in order, and the second substrate material layer has a second contact conductor disposed therein. A portion of the first substrate material layer is removed to form a first substrate, wherein the first contact conductor is exposed to a surface of the first substrate away from the first interconnect structure. The second wafer is covered on the first substrate such that the first contact conductor is directly physically in contact with the second pad.

What is claimed is: 
     
         1 . A manufacturing method of a die-stack structure, comprising:
 providing a first wafer comprising a first die, wherein the first die comprises a first substrate material layer, a first interconnect structure, and a first pad, and the first interconnect structure and the first pad are formed on the first substrate material layer in order, and the first substrate material layer has a first contact conductor disposed therein;   providing a second wafer comprising a second die, wherein the second die comprises a second substrate material layer, a second interconnect structure, and a second pad, and the second interconnect structure and the second pad are formed on the second substrate material layer in order, and the second substrate material layer has a second contact conductor disposed therein;   removing a portion of the first substrate material layer to form a first substrate, wherein the first contact conductor is exposed to a surface of the first substrate away from the first interconnect structure; and   covering the second wafer on the first substrate such that the first contact conductor is directly physically in contact with the second pad.   
     
     
         2 . The manufacturing method of the die-stack structure of  claim 1 , wherein the first contact conductor does not cover the surface of the first substrate away from the first interconnect structure. 
     
     
         3 . The manufacturing method of the die-stack structure of  claim 1 , further comprising:
 disposing the first wafer on a carrier plate before the portion of the first substrate material layer is removed.   
     
     
         4 . The manufacturing method of the die-stack structure of  claim 3 , wherein the carrier plate comprises a carrier wafer, the carrier wafer comprises a third die, and the first pad of the first die is connected to a pad of the third die. 
     
     
         5 . The manufacturing method of the die-stack structure of  claim 1 , wherein an active surface of the second die faces a back of the first die. 
     
     
         6 . The manufacturing method of the die-stack structure of  claim 1 , further comprising:
 forming a dielectric layer on the surface of the first substrate away from the first interconnect structure after the portion of the first substrate material layer is removed, wherein the dielectric layer exposes the first contact conductor.