Integrated Fan-Out Package with 3D Magnetic Core Inductor

Abstract

Among other things, a method of fabricating an integrated electronic device package is described. First trace portions of an electrically conductive trace are formed on an electrically insulating layer of a package structure, and vias of the conductive trace are formed in a sacrificial layer disposed on the electrically insulating layer. The sacrificial layer is removed, and a die is placed above the electrically insulating layer. Molding material is formed around exposed surfaces of the die and exposed surfaces of the vias, and a magnetic structure is formed within the layer of molding material. Second trace portions of the electrically conductive trace are formed above the molding material and the magnetic structure. The electrically conductive trace and the magnetic structure form an inductor. The electrically conductive trace may have a coil shape surrounding the magnetic structure. The die may be positioned between portions of the inductor.

What is claimed is: 
     
         1 . A method comprising:
 forming a molding material around a die and vias;   forming a magnetic structure within the molding material; and   forming an electrically conductive trace covering a top surface of the molding material, wherein the electrically conductive trace and the magnetic structure form an inductor.   
     
     
         2 . The method of  claim 1 , the electrically conductive trace having a coil shape and surrounding the magnetic structure. 
     
     
         3 . The method of  claim 1 , wherein the magnetic structure comprises at least one material selected from the group consisting of CuFe 2 O 4 , BiFe 5 O 12 , NiFe alloy, and CoTaZr alloy. 
     
     
         4 . The method of  claim 1 , wherein the magnetic structure comprises in atomic percentage about 40% Ni, about 40% Zn, and about 20% CuFe 2 O 4 . 
     
     
         5 . The method of  claim 1 , wherein the magnetic structure comprises in atomic percentage about 80% Y and about 20% BiFe 5 O 12 . 
     
     
         6 . The method of  claim 1 , wherein the magnetic structure comprises an alloy in atomic percentage of about 91.5% Co, about 4.5% Ta, and about 4% Zr. 
     
     
         7 . The method of  claim 1 , the inductor having a toroidal shape. 
     
     
         8 . The method of  claim 1 , the magnetic structure having a closed loop shape. 
     
     
         9 . The method of  claim 1 , the die being disposed between portions of the inductor. 
     
     
         10 . The method of  claim 1 , further comprising:
 forming the vias in a sacrificial layer disposed on an electrically insulating layer, the vias being electrically connected to the electrically conductive trace; and   removing the sacrificial layer and placing the die above the electrically insulating layer, wherein the sacrificial layer comprises photoresist.   
     
     
         11 . A method comprising:
 forming a molding material around a die and vias;   forming a magnetic material in the molding material; and   forming trace portions covering a top surface of the molding material, the vias and the trace portions surrounding the magnetic material.   
     
     
         12 . The method of  claim 11 , wherein the magnetic material comprises at least one material selected from the group consisting of CuFe 2 O 4 , BiFe 5 O 12 , NiFe alloy, and CoTaZr alloy. 
     
     
         13 . The method of  claim 11 , wherein the magnetic material comprises in atomic percentage about 40% Ni, about 40% Zn, and about 20% CuFe 2 O 4 . 
     
     
         14 . The method of  claim 11 , wherein the magnetic material comprises in atomic percentage about 80% Y and about 20% BiFe 5 O 12 . 
     
     
         15 . The method of  claim 11 , wherein the magnetic material comprises an alloy in atomic percentage of about 91.5% Co, about 4.5% Ta, and about 4% Zr. 
     
     
         16 . The method of  claim 11 , the trace portions and the vias having a toroidal shape. 
     
     
         17 . The method of  claim 11 , the die being disposed between the trace portions and the vias. 
     
     
         18 . The method of  claim 11 , further comprising:
 forming the vias in a sacrificial layer disposed on a first electrically insulating layer, the vias being electrically connected to the trace portions;   removing the sacrificial layer and forming a second electrically insulating layer on the first electrically insulating layer; and   placing the die above the second electrically insulating layer, wherein the sacrificial layer comprises photoresist.   
     
     
         19 . A method comprising:
 forming a molding material around vias;   planarizing the molding material;   forming a magnetic material in the molding material; and   forming trace portions covering a top surface of the molding material, the vias and the trace portions surrounding the magnetic material.   
     
     
         20 . The method of  claim 19 , further comprising forming the vias in a sacrificial layer disposed on an electrically insulating layer by:
 forming a seeding layer on the sacrificial layer; and   forming a conductive layer on the seeding layer.