# US 5,699,605 A · Method for forming a magnetic thin film head with recessed basecoat

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- Number: US 5,699,605 A
- Document ID: US5699605A
- Status: Granted
- Kind: A
- Application number: 08/421,429
- Filed: 1995-04-12
- Granted: 1997-12-23
- Earliest claimed: 1994-05-23
- Assignees: Seagate Technology LLC
- Inventors: Nurul Amin; John Bortins; Ying Yan
- Web page: https://patentgrep.com/patent/US5699605A

## CPC

- G11B 5/3163: {Fabrication methods or processes specially adapted for a particular head structure, e.g. using base layers for electroplating, using functional layers for masking, using energy or particle beams for shaping the structure or modifying the properties of the basic layers}
- G11B 5/3103: {Structure or manufacture of integrated heads or heads mechanically assembled and electrically connected to a support or housing}
- G11B 5/313: {Disposition of layers}
- Y10T 29/49044: Plural magnetic deposition layers
- G11B: INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER (recording measured values in a way that does not require playback through a transducer G01D9/00; recording or playback apparatus using mechanically marked tape, e.g. punched paper tape, or using unit records, e.g. punched or magnetically marked cards G06K; transferring data from one type of record carrier to another G06K1/18; circuits for coupling output of reproducer to radio receiver H04B1/20; gramophone pick-ups or like acoustic electromechanical transducers or circuits therefor H04R)
- Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION

## Abstract

A thin film magnetic head is carried in a recessed region which is etched in a basecoat. The thin film magnetic head includes upper and lower pole pieces having an upper pole tip and a lower pole tip, respectively. The upper and lower pole tips form a magnetic flux gap. Electrical conductors are carried in an insulating layer between the upper and lower pole pieces. The magnetic flux gap defines a plane which is generally parallel with a plane defined by the conductors. The electrical conductors lie on either side of the plane.

## Claims

### Claim 1

A method of forming a thin film magnetic head, comprising:
depositing a basecoat on a substantially planar substrate;
forming a recessed region in the basecoat, wherein the recessed region has a depth;
depositing a magnetic bottom pole piece having a bottom pole leg and a bottom pole tip on th basecoat, wherein the bottom pole leg is deposited in the recessed region of the basecoat;
depositing insulating material on the magnetic bottom pole piece, wherein the insulating material has a plurality of electrical conductors extending therethrough; and
depositing a magnetic upper pole piece having an upper pole leg overlying the bottom pole leg and an upper tip overlying the bottom pole tip forming a transducing gap for reading and writing magnetically encoded information, wherein the transducing gap defines a plane through the thin film magnetic head and the upper and bottom pole pieces are generally symmetric about the plane.

### Claim 2 (depends on 1)

The method of claim 1 wherein depositing the magnetic bottom pole piece comprises depositing the magnetic bottom pole piece to a thickness approximately equal to the depth of the recessed region.

### Claim 3 (depends on 1)

The method of claim 1 wherein forming a recessed region comprises:
depositing a mask on the basecoat;
removing an exposed portion of the basecoat through the mask; and
removing the mask.

### Claim 4 (depends on 1)

The method of claim 1 wherein removing an exposed portion of the basecoat comprises applying a chemical etch.

### Claim 5 (depends on 1)

The method of claim 1 wherein removing an exposed portion of the basecoat comprises ion milling the basecoat.

### Claim 6 (depends on 1)

The method of claim 1 including depositing a film in the recessed region whereby the shape of the recessed region is altered.

### Claim 7 (depends on 6)

The method of claim 6 wherein depositing a film comprises sputtering a film.

### Claim 8 (depends on 1)

The method of claim 1 including depositing a second basecoat layer in the recessed region whereby slope of side walls of the recessed region are increased.

### Claim 9 (depends on 1)

The method of claim 1 wherein the step of forming a recessed region in the basecoat includes forming sides that are substantially perpendicular to the plane of the substrate; and further comprising the step of depositing an encapsulation layer over the basecoat in the recessed region, the encapsulation layer having an outer surface with sloping sides which form an angle with the plane of the substrate of substantially less than ninety degrees.