Method of making a multi-channel time based servo tape media

Abstract

A thin film magnetic recording head is fabricated by forming a substrate from opposing ferrite blocks which have a ceramic member bonded between them. This structure is then diced to form a plurality of columns, wherein each column has a ferrite/ceramic combination. Each column represents a single channel in the completed head. A block of ceramic is then cut to match the columned structure and the two are bonded together. The bonded structure is then cut or ground until a head is formed, having ceramic disposed between each channel. A ferrite back-gap is then added to each channel, minimizing the reluctance of the flux path. The thin film is patterned on the head to optimize various channel configurations.

1 . A multi-channel surface film magnetic recording head comprising:
 a plurality of magnetically permeable columns, each column being divided into two parts by a substantially magnetically impermeable gap member, the gap member forming a sub-gap on a writing side of the head;   at least one magnetically impermeable barrier, located between and magnetically isolating the plurality of magnetically permeable columns from one another; and   a magnetically permeable thin film layer spanning at least a portion of the sub-gap and magnetically coupling the two parts of each column.   
     
     
         2 . The magnetic recording head of  claim 1 , further comprising:
 a plurality of magnetically permeable back-bars, wherein each magnetically permeable column has a back-bar coupled to it and the back-bar bypasses the magnetically impermeable gap member at one end of the magnetically permeable column.   
     
     
         3 . The magnetic recording head of  claim 2 , wherein each back-bar is a substantially U shaped ferrite block. 
     
     
         4 . The magnetic recording head of  claim 2 , further comprising:
 a single coil wrapped about each of the back-bars.   
     
     
         5 . The magnetic recording head of  claim 2 , further comprising:
 a plurality of coils wherein each back-bar has a single coil wrapped about it   
     
     
         6 . The magnetic recording head of  claim 1  wherein the magnetically impermeable barrier is ceramic. 
     
     
         7 . The magnetic recording head of  claim 1  wherein the thin film layer is located over an entire upper surface of the recording head. 
     
     
         8 . The magnetic recording head of  claim 1  wherein the thin film layer is located only over a portion of the recording head, the portion being the area between air bleed slots cut into the head. 
     
     
         9 . The magnetic recording head of  claim 1  wherein the thin film layer has been removed in portions so as to magnetically isolate each of the magnetically permeable columns. 
     
     
         10 . A method of making a multi-channel surface film magnetic recording head, comprising:
 forming a sub-gap substrate by bonding a ceramic member between two magnetically permeable blocks;   cutting the substrate to form a plurality of columns, wherein each column is divided by a portion of the ceramic member;   providing a ceramic block having a plurality of notches corresponding to the plurality of columns;   bonding the columns within the notches to form a head member;   processing the head member so that the head member has alternating sections of the ceramic and the columns with the columns extending therethrough;   coupling at least one winding to a first side of the columns; and   forming writing gaps in a second side of the columns.   
     
     
         11 . The method of  claim 10  wherein bonding the columns within the notches includes:
 providing glass within the notches; 
 heating the glass so as to melt the glass; 
 allowing the melted glass to wick between the notches and the columns; and 
 allowing the glass to cool thereby forming a bond. 
 
     
     
         12 . The method of  claim 10  wherein processing the head member includes cutting a top and bottom portion of the head member to expose portions of the columns in both the top and bottom portion. 
     
     
         13 . The method of  claim 10  wherein coupling a winding further includes;
 coupling a back-bar to each of the columns; and 
 winding the coil about the back-bar. 
 
     
     
         14 . The method of  claim 13  wherein the back-bar is formed from a continuous piece of magnetically permeable material. 
     
     
         15 . The method of  claim 10  wherein forming writing gaps further includes:
 forming a magnetically permeable surface thin film; and 
 creating gaps in the thin film. 
 
     
     
         16 . The method of  claim 15  wherein the thin film is foamed over an entire upper surface of the head. 
     
     
         17 . The method of  claim 15  wherein the thin film is only located between air bleed slots cut into the head. 
     
     
         18 . The method of  claim 15  wherein the thin film is absent in strips between each column thereby magnetically isolating each column. 
     
     
         19 . A surface film magnetic recording head comprising:
 a magnetically permeable core;   a substantially magnetically impermeable member dividing the core into two poles and forming a sub-gap;   a magnetically permeable thin film coupling the two poles across the sub-gap, wherein the thin film includes at least one writing gap; and   a back-bar, formed from magnetically permeable material, the back bar bypassing the impermeable member to complete a magnetic circuit between the two poles.   
     
     
         20 . The surface film magnetic recording head of  claim 19 , wherein the core and back-bar are formed from ferrite. 
     
     
         21 .- 51 . (canceled)