Thin-film coil, magnetic head, method of manufacturing the thin-film coil, and method of manufacturing the magnetic head

Abstract

The invention seeks to provide a thin-film coil of high space factor and of a low resistance in an easy and reliable manner. In a thin-film coil in which a first coil and a second coil each having a desired number of winding are electrically connected in series and mounted in the thin-film coil, the second coil is formed between winding portions of the first coil on substantially the same plane, and only an insulating film is interposed between the first coil and the second coil.

What is claimed is:  
     
         1 . A thin-film coil in which a first coil and a second coil each having a desired number of winding are electrically connected in series, wherein: 
 the second coil is formed between winding portions of the first coil on substantially the same plane, and    only an insulating film is interposed between the first coil and the second coil.    
     
     
         2 . The thin-film coil according to  claim 1 , wherein at least a cross section of the first coil is substantially a trapezoid.  
     
     
         3 . A magnetic head having a thin-film coil in which a first coil and a second coil each having a desired number of winding are electrically connected in series and having a magnetic core, wherein: 
 the second coil is formed between winding portions of the first coil on substantially the same plane, and    only an insulating film is interposed between the first coil and the second coil.    
     
     
         4 . The magnetic head according to  claim 3 , wherein at least a cross section of the first coil is substantially a trapezoid.  
     
     
         5 . A method of manufacturing a thin-film coil, comprising the steps of: 
 forming a first coil having a predetermined number of winding via a first insulating film;    forming a second insulating film on a surface of the first coil and between its winding portions;    forming an underlying conductive film on the second insulating film, and treating the underlying conductive film so as to leave only its bottom portions between the winding portions of the first coil; and    growing deposition originating from a remaining portion of the underlying conductive film on the bottom portions between the winding portions of the first coil so as to form a second coil.    
     
     
         6 . The method of manufacturing a thin-film coil according to  claim 5 , wherein the second coil is formed by deposition by means of an electroplating process.  
     
     
         7 . The method of manufacturing a thin-film coil according to  claim 5 , wherein the step of treating the underlying conductive film so as to leave only its bottom portions between winding portions of the first coil is carried out by means of an ion etching process with a predetermined angle.  
     
     
         8 . The method of manufacturing a thin-film coil according to  claim 5 , wherein the step of treating the underlying conductive film so as to leave only its bottom portions between winding portions of the first coil is carried out by means of a wet etching process.  
     
     
         9 . The method of manufacturing a thin-film coil according to  claim 5 , wherein the second insulating film between the first coil and the second coil is formed by means of one of a sputtering process and a vapor deposition process.  
     
     
         10 . A method of manufacturing a magnetic head, comprising the steps of: 
 forming a first coil having a predetermined number of winding via a first insulating film;    forming a second insulating film on a surface of the first coil and between its winding portions;    forming an underlying conductive film on the second insulating film, and treating the underlying conductive film so as to leave only its bottom portions between the winding portions of the first coil; and    growing deposition originating from a remaining portion of the underlying conductive film on the bottom portions between the winding portions of the first coil so as to form a second coil.    
     
     
         11 . The method of manufacturing a magnetic head according to  claim 10 , wherein the second coil is formed by deposition by means of an electroplating process.  
     
     
         12 . The method of manufacturing a magnetic head according to  claim 10 , wherein the step of treating the underlying conductive film so as to leave only its bottom portions between winding portions of the first coil is carried out by means of an ion etching process with a predetermined angle.  
     
     
         13 . The method of manufacturing a magnetic head according to  claim 10 , wherein the step of treating the underlying conductive film so as to leave only its bottom portions between winding portions of the first coil is carried out by means of a wet etching process.  
     
     
         14 . The method of manufacturing a magnetic head according to  claim 10 , wherein the second insulating film between the first coil and the second coil is formed by means of one of a sputtering process and a vapor deposition process.