Method for forming a magnetic pole by patterning a mask layer and a metal layer

Claim 1

A method for forming a lower magnetic pole in a thin film magnetic head from a metal layer, the lower magnetic pole having a shape which allows an easy formation of a thin uniform insulation layer on top thereof, the method comprising the steps of: (a) preparing a substrate with the metal layer formed thereon; (b) forming a mask layer on top of the metal layer; (c) forming a photoresist layer on top of the mask layer; (d) exposing a light beam to a portion of the photoresist so as to define a size of the lower magnetic pole; (e) removing the portion of the photoresist by using a developer, and etching the mask layer by using an etchant until one half of the mask layer under the portion is removed; (f) exposing a light beam to a part of the remaining portion of the photoresist layer so as to define a tip area of the lower magnetic pole; (g) removing the part of the remaining portion of the photoresist by using a developer and etching the mask layer until the top surface of the metal layer is exposed to thereby obtain a patterned mask layer, wherein the patterned mask layer includes a bottom surface and a first and a second sloping walls, each of the sloping walls being inclined at a first predetermined angle with respect to the bottom surface of the patterned mask layer, respectively; and (h) dry-etching the metal layer by using the patterned mask layer, thereby providing the lower magnetic pole with a bottom surface, a first and a second inclined walls, each of the inclined walls being inclined at a second predetermined angle with respect to the bottom surface of the lower magnetic pole, respectively, wherein the second predetermined angle is controlled by changing the ratio of the etching rate of the metal layer to that of the mask layer.

Claim 2

A method for forming a lower magnetic pole in a thin film magnetic head from a metal layer, the lower magnetic pole having a shape which allows an easy formation of a thin uniform insulation layer on top thereof, the method comprising the steps of: (a) preparing a substrate with the metal layer formed thereon; (b) forming a mask layer on top of the metal layer; (c) forming a photoresist layer on top of the mask layer; (d) exposing a light beam to a portion of the photoresist so as to define a size of the lower magnetic pole; (e) removing the portion of the photoresist by using a developer, and etching the mask layer by using an etchant until one half of the mask layer under the portion is removed; (f) exposing a light beam to a part of the remaining portion of the photoresist layer so as to define a tip area of the lower magnetic pole; (g) removing the part of the remaining portion of the photoresist by using a developer and etching the mask layer until the top surface of the metal layer is exposed to thereby obtain a patterned mask layer, wherein the patterned mask layer includes a bottom surface and a first and a second sloping walls, each of the sloping walls being inclined at a first predetermined angle with respect to the bottom surface of the patterned mask layer, respectively; and (h) dry-etching the metal layer by using the patterned mask layer, thereby providing the lower magnetic pole with a bottom surface, a first and a second inclined walls, each of the inclined walls being inclined at a second predetermined angle with respect to the bottom surface of the lower magnetic pole, respectively, wherein the second predetermined angle is controlled by changing the ratio of the etching rate of the metal layer to that of the mask layer.

Claim 9

A method for forming a lower magnetic pole in a thin film magnetic head, said method comprising the steps of: (a) providing a substrate having a metal layer thereon; (b) forming a mask layer atop said metal layer, said mask layer having a top surface, a bottom surface, and a first thickness therebetween, said first thickness being greater than a thickness of said metal layer; (c) forming a photoresist layer atop the mask layer; (d) removing a first portion of the photoresist layer to expose a first portion of the mask layer; (e) etching said first portion of the mask layer down to approximately one-half of said first thickness; (f) removing a second portion of the photoresist layer to expose a second portion of said mask layer; (g) continuing to etch said first portion of the mask layer until reaching said metal layer while simultaneously etching said second portion of said mask layer down to approximately one-half of said first thickness, such that a first sloping wall extending from said metal layer to said top surface, and a second sloping wall extending from said etched second portion of the mask layer to said top surface are formed, said first and second sloping walls being sloped at a substantially same first angle; (h) removing any photoresist material remaining atop said mask layer; and (i) etching both the metal layer and the mask layer such that a lower magnetic pole having a bottom surface and at least one inclined wall is formed, said at least one inclined wall being sloped at a second angle which is less steep than said first angle, and wherein the second angle is determined by controlling a ratio of the etching rate of the metal layer to the etching rate of the mask layer.

Claim 10

A method for forming a lower magnetic pole in a thin film magnetic head, said method comprising the steps of: (a) providing a substrate having a metal layer thereon; (b) forming a mask layer atop said metal layer, said mask layer having a top surface, a bottom surface, and a first thickness therebetween, said first thickness being greater than a thickness of said metal layer; (c) forming a photoresist layer atop the mask layer; (d) removing a first portion of the photoresist layer to expose a first portion of the mask layer; (e) etching said first portion of the mask layer down to approximately one-half of said first thickness; (f) removing a second portion of the photoresist layer to expose a second portion of said mask layer; (g) continuing to etch said first portion of the mask layer until reaching said metal layer while simultaneously etching said second portion of said mask layer down to approximately one-half of said first thickness, such that a first sloping wall extending from said metal layer to said top surface, and a second sloping wall extending from said etched second portion of the mask layer to said top surface are formed, said first and second sloping walls being sloped at a substantially same first angle; (h) removing any photoresist material remaining atop said mask layer; and (i) etching both the metal layer and the mask layer such that a lower magnetic pole having a bottom surface and at least one inclined wall is formed, said at least one inclined wall being sloped at a second angle which is less steep than said first angle, and wherein the second angle is determined by controlling a ratio of the etching rate of the metal layer to the etching rate of the mask layer.