Method of manufacturing a magnetic head

• US 6,238,731 B1
• Filed: 09/07/1999
• Issued: 05/29/2001
• Est. Priority Date: 12/01/1992
• Status: Expired due to Fees

• Current Assignee: US Philips Corporation (Koninklijke Philips N.V.)
• Original Assignee: US Philips Corporation (Koninklijke Philips N.V.)
• Inventors: Van Der Zaag, Pieter J., Wolf, Ronald M., Cillessen, Johannes F. M., Ruigrok, Jacobus J. M., Folkerts, Wiepke, Postma, Lambertus
• Primary Examiner(s): PIANALTO, BERNARD D
• Application Number:
  US09/390,854
• Time in Patent Office: 630 Days
• Field of Search: 427/130, 427/419.2, 427/131, 427/404, 427/132, 427/127, 427/355, 427/265, 427/271, 204/192.22
• US Class Current: 427/130
• CPC Class Codes: G11B 5/3919 the guide being interposed in the flux path
• CPC Class Codes: G11B 5/3922 the read-out elements being disposed in magnetic shunt relative to at least two parts of the flux guide structure

Abstract

Thin-film magnetic head having a head face (103) and comprising a magnetoresistive element (109) oriented transversely to the head face and a flux-guiding element (107) of a magnetically permeable material terminating in the head face. A peripheral area (109a) of the magnetoresistive element extending parallel to the head face is present opposite the flux-guiding element for forming a magnetic connection between the magnetoresistive element and the flux-guiding element. The flux-guiding element and the peripheral area of the magnetoresistive element constitute a common magnetic contact face (111), while the magnetically permeable material of the flux-guiding element is electrically insulating.

Claims

1. A method of manufacturing a magnetic head comprising the steps of:

providing a first thin layer of magnetically permeable and electrically insulating material;

at least partly flattening a portion of the first layer for forming a first component of the magnetic head; and

forming a second layer of magnetically and electrically conducting material for forming a magnetoresistive element of the head, including a peripheral area directly formed on the at least partially flat portion of the first component and constituting a common magnetic contact face between the magnetoresistive element and the first component to produce the magnetic head.

2. The method of claim 1, in which the magnetically permeable and electrically insulating material includes an oxidic soft-magnetic material.

3. The method of claim 2, in which the oxidic soft-magnetic material includes a ferrite.

4. The method of claim 3, in which the ferrite includes a MnZn ferrite or a NiZn ferrite.

5. The method of claim 2, in which the oxidic soft-magnetic material includes a garnet.

6. The method of claim 1, further comprising the step of forming a layer of a synthetic resin across the magnetoresistive element after forming the magnetoresistive element.

7. The method of claim 6 in which forming the layer of synthetic resin includes deposition onto the magnetoresistive element.

8. The method of claim 1, wherein a number of parameters relating to the magnetic head has been chosen in such a way that the following condition is satisfied:

${\mathrm{\rho <br><br>}}_f=c*\left(\frac{t_1*h_1}{t_m*b}\right)*{\mathrm{\rho <br><br>}}_m$

in which;

c is a numerical value of more than ⅓

,

p_f is the resistivity of the magnetically permeable and electrically insulating material,

p_m is the resistivity of the magnetically permeable and electrically insulating material,

t₁ is the thickness, in a direction transverse to the magnetoresistive element, of the first component,

t_m is the thickness of the magnetoresistive element,

h₁ is the height, from the head face, of the first component, and

b is the width, in a direction transverse to the head face, of the magnetoresistive element.

9. The method of claim 8, wherein the numerical value c is larger than 3.

10. The method of claim 1, wherein the method further comprises:

forming a second component of a magnetically permeable material opposite a further peripheral area of the magnetoresistive element, wherein the further peripheral area and the second component constitute a further common magnetic contact face and wherein the magnetic head is dimensioned in such a way that the magnetically permeable material of the first and second components satisfies the condition ${\mathrm{\rho <br><br>}}_f=c*\left(\frac{t_1*h_1+t_2*h_2}{t_m*b}\right)*{\mathrm{\rho <br><br>}}_m$

in which;

c is the numerical value of more than ⅓

,

p_f is the resistivity of the magnetically permeable and electrically insulating material,

p_m is the resistivity of the magnetically permeable and electrically insulating material,

t₁ and t₂ are the thickness, in a direction transverse to the magnetoresistive element, of the first and second component, respectively,

h₁ is the height, measured perpendicular from the head face, of the first component,

h₂ is the height, in a direction perpendicular to the head face and measured from an edge of the magnetoresistive element that is opposite from the first component, of the second component, or the width, measured parallel to the head face, of the second component if this width is smaller than the height of the second component.

11. The method of claim 10, wherein the numerical value c is larger than 3.

13. The method of claim 1, in which the flattening includes mechanical polishing.

14. The method of claim 1 in which forming the magnetoresistive element includes thin-film deposition onto the flattened surface.

12. The method of claim in which the first layer is formed by depositing a thin-film on a surface.

15. A method of manufacturing a thin film magnetic head comprising the steps of:

providing an irregular element surface;

depositing on the element surface, a first layer of first material having low magnetic permeability and low electrical conductance;

depositing on the first layer, a second layer of second material having high magnetic permeability and low electrical conductance so as to form an intermediate structure of two layers;

flattening the intermediate structure to form a flattened surface for producing a first component of the second material; and

forming a magnetoresistive element directly on the first component, the material of the magnetoresistive element having high electrical conductivity and high permeability for forming the magnetic head.

16. The method of claim 15 in which:

providing the irregular surface includes providing a substrate of magnetically conductive and electrically insulating material;

providing an irregular surface further includes forming a conductor on the substrate by depositing a conductive material on the substrate;

providing the irregular surface further includes forming a recess in the substrate by reactive ion etching;

the conductor is formed on the surface of the substrate in the recess;

the flattening of the intermediate structure forms a second component from the material of the substrate or from the second layer of second material, the magnetoresistive element is deposited directly on at least a portion of the first component and at least a portion of the second component;

the material of the substrate is MnZn ferrite or NiZn ferrite;

the material of the conductor is Al;

the conductor is coated with Mo;

the material of the first layer is ZrO2 or SiO₂ deposited in a thin-film by sputter ablation;

the material of the second layer is an oxidic magnetically-soft material;

the oxidic magnetically soft material of the second layer is MnZn ferrite or NiZn ferrite or a garnet;

the material of the second layer is the same as the material of the substrate;

the flattening is performed by polishing;

the material of the magnetoresistive element is a NiFe alloy; and

the method further comprises the step of depositing a layer of synthetic resin across the magnetoresistive element.