# US 8,540,852 B2 · Method and apparatus for manufacturing magnetoresistive devices

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- Number: US 8,540,852 B2
- Document ID: US8540852B2
- Status: Granted
- Kind: B2
- Application number: 11/991,967
- Filed: 2006-09-13
- Published: 2010-06-24
- Granted: 2013-09-24
- Earliest claimed: 2005-09-13
- Assignees: Canon Anelva Corporation
- Applicants: Naoki Watanabe; Yoshimitsu Kodaira; David D. Djayaprawira; Hiroki Maehara
- Inventors: Naoki Watanabe; Yoshimitsu Kodaira; David D. Djayaprawira; Hiroki Maehara
- Web page: https://patentgrep.com/patent/US8540852B2

## CPC

- H10N 50/01: Manufacture or treatment
- B82Y 10/00: Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
- B82Y 25/00: Nanomagnetism, e.g. magnetoimpedance, anisotropic magnetoresistance, giant magnetoresistance or tunneling magnetoresistance
- B82Y 40/00: Manufacture or treatment of nanostructures
- G01R 33/093: {using multilayer structures, e.g. giant magnetoresistance sensors (thin magnetic films H01F10/00)}
- G11B 5/3906: {Details related to the use of magnetic thin film layers or to their effects}
- G11B 5/3909: {Arrangements using a magnetic tunnel junction}
- H01F 10/3254: {the spacer being semiconducting or insulating, e.g. for spin tunnel junction [STJ]}
- H01F 41/308: {lift-off processes, e.g. ion milling, for trimming or patterning}
- 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 2005/3996: {large or giant magnetoresistive effects [GMR], e.g. as generated in spin-valve [SV] devices}
- H01F 10/3259: {Spin-exchange-coupled multilayers comprising at least a nanooxide layer [NOL], e.g. with a NOL spacer}
- H01F 10/3272: {by use of anti-parallel coupled [APC] ferromagnetic layers, e.g. artificial ferrimagnets [AFI], artificial [AAF] or synthetic [SAF] anti-ferromagnets}
- H10N: ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- B82Y: SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12)
- 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)
- H01F: MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES

## Abstract

Disclosed are method and apparatus for manufacturing a magnetoresistive device which are suitable for manufacturing a high-quality magnetoresistive device by reducing damages caused during the processing of a multilayer magnetic film as a component of the magnetoresistive device, thereby preventing deterioration of magnetic characteristics due to such damages. Specifically disclosed is a method for manufacturing a magnetoresistive device, which includes processing a multilayer magnetic film by performing a reactive ion etching on a substrate which is provided with the multilayer magnetic film as a component of the magnetoresistive device. This method for manufacturing a magnetoresistive device includes irradiating the multilayer magnetic film with an ion beam after the reactive ion etching.

## Claims

### Claim 1

A method for manufacturing magnetoresistive devices, each of the devices having a multilayer magnetic film formed on a substrate so that the formed multilayer magnetic film can act as a magnetoresistive device, the method comprising:
processing the multilayer magnetic film through a reactive ion etching process using an etching gas including alcohol containing at least one or more hydroxyl groups; and
removing a damaged layer formed in the reactive ion etching process by etching the formed multilayer magnetic film using irradiation of ion beams which have accelerating voltages between 50 and 200 V and ion currents between 50 and 200 mA.

### Claim 2 (depends on 1)

The method as defined in claim 1, wherein the irradiating the formed multilayer magnetic film with ion beams includes exposing the formed multilayer magnetic film to the ion beams at any of the incident angles between 5 and 80 degrees with regard to the surface of the formed multilayer magnetic film.

### Claim 3 (depends on 1)

The method as defined in claim 1, wherein the irradiating the formed multilayer magnetic film with ion beams includes exposing the formed multilayer magnetic film to the ion beams at any of the incident angles between 30 and 60 degrees with regard to the surface of the formed multilayer magnetic film.

### Claim 4 (depends on 1)

The method as defined in claim 1, wherein the irradiating the formed multilayer magnetic film with ion beams includes exposing the formed multilayer magnetic film to the ion beams by permitting the substrate having the multilayer magnetic film formed thereon to rotate.

### Claim 5 (depends on 1)

The method as defined in claim 1, wherein the irradiating the formed multilayer magnetic film with ion beams is followed by forming a protective film, wherein the irradiating the formed multilayer magnetic film with ion beams and the forming a protective film being performed under a sustained vacuum condition.

### Claim 6 (depends on 5)

The method as defined in claim 5, wherein the forming a protective film is performed by permitting a sputtering process to take place in the high frequency range of between above 1 KHz and below 100 MHz and in the high pressure vacuum range of between above 1 Pa and below 20 Pa.