Planar magnetic inductor and method for manufacturing the same

Abstract

A planar magnetic inductor and a method for manufacturing the same are provided. The planar magnetic inductor comprises an insulating oxide magnetic layer formed on a substrate, a conductive coil separated from a lower surface of the insulating oxide magnetic layer while being completely embedded in the insulating oxide magnetic layer, and a cover layer formed on the insulating oxide magnetic layer for protecting the insulating oxide magnetic layer. The insulating oxide magnetic layer comprises a lower insulating oxide magnetic layer, and an upper insulating oxide magnetic layer formed on the lower insulating oxide magnetic layer, such that the conductive coil is completely embedded in the upper insulating oxide magnetic layer. The planar magnetic inductor can realize excellent high frequency characteristics and high inductance with a reduced scale.

1 . A planar magnetic inductor, comprising: 
 an insulating oxide magnetic layer formed on a substrate;    a conductive coil separated from a lower surface of the insulating oxide magnetic layer while being completely embedded in the insulating oxide magnetic layer; and    a cover layer formed on the insulating oxide magnetic layer for protecting the insulating oxide magnetic layer.    
   
   
       2 . The inductor as set forth in  claim 1 , wherein the insulating oxide magnetic layer comprises a lower insulating oxide magnetic layer formed on the substrate, and an upper insulating oxide magnetic layer formed on the lower insulating oxide magnetic layer, such that the conductive coil is formed on the lower insulating oxide magnetic layer while being completely embedded in the upper insulating oxide magnetic layer.  
   
   
       3 . The inductor as set forth in  claim 1 , wherein the insulating oxide magnetic layer comprises an oxide magnetic material comprising at least two elements selected from the group comprising Fe, Ni, Zn, Mn, Mg, Co, Ba and Sr.  
   
   
       4 . The inductor as set forth in  claim 3 , wherein the insulating oxide magnetic layer is formed of Ni—Zn ferrite.  
   
   
       5 . The inductor as set forth in  claim 1 , wherein the insulating oxide magnetic layer is formed by ferrite plating.  
   
   
       6 . The inductor as set forth in  claim 1 , wherein the cover layer comprises a material selected from polymeric material, ceramic material, glass, silicone, or a combination thereof.  
   
   
       7 . The inductor as set forth in  claim 6 , wherein the cover layer comprises polyimide.  
   
   
       8 . The inductor as set forth in  claim 1 , wherein the conductive coil is a spiral coil formed of copper.  
   
   
       9 . The inductor as set forth in  claim 1 , wherein the conductive coil is formed by electroplating, and the planar magnetic inductor further comprises a plating seed layer pattern having the same pattern as that of the conductive coil and formed underneath the conductive coil.  
   
   
       10 . A method for manufacturing a planar magnetic inductor is provided, comprising: 
 forming a lower insulating oxide magnetic layer on a substrate;    forming a conductive coil on the lower insulating oxide magnetic layer;    forming an upper insulating oxide magnetic layer directly on the conductive coil such that the conductive coil is completely embedded in the upper insulating oxide magnetic layer; and    forming a cover layer on the upper insulating oxide magnetic layer.    
   
   
       11 . The method as set forth in  claim 10 , wherein the upper and lower insulating oxide magnetic layers comprise an oxide magnetic material comprising at least two elements selected from the group comprising Fe, Ni, Zn, Mn, Mg, Co, Ba and Sr.  
   
   
       12 . The method as set forth in  claim 10 , wherein the conductive coil is formed by electroplating.  
   
   
       13 . The method as set forth in  claim 12 , wherein formation of the conductive coil comprises: 
 forming a coil-shaped photoresist layer pattern on the lower insulating oxide magnetic layer;    forming a coil-shaped plating seed layer pattern by use of the photoresist pattern; and    forming the conductive coil on the plating seed layer pattern by electroplating.    
   
   
       14 . The method as set forth in  claim 12 , wherein formation of the conductive coil comprises: 
 forming the plating seed layer on the lower insulating oxide magnetic layer;    forming a photoresist layer mold having a coil-shaped pattern on the plating seed layer;    forming the conductive coil by electroplating using the photoresist layer mold as a mask; and    removing the photoresist layer mold and a portion of the plating seed layer under the photoresist layer mold.    
   
   
       15 . The method as set forth in  claim 10 , wherein formation of the conductive coil comprises: 
 cladding a metallic thin film onto the lower insulating oxide magnetic layer by compression; and    performing selective chemical etching on the metallic thin film to form a coil pattern.    
   
   
       16 . The inductor as set forth in  claim 10 , wherein formation of the conductive coil comprises: 
 forming a screen for a coil pattern on the lower insulating oxide magnetic layer; and    printing a conductive paste on the lower insulating oxide magnetic layer by using the screen as a print mask.    
   
   
       17 . The method as set forth in  claim 10 , wherein formation of the conductive coil comprises: 
 printing a conductive paste in a slurry state on the lower insulating oxide magnetic layer by ink-jet printing.