Improved performance of Cu-Co CPP GMR sensors

Journal Article · Mon Sep 01 04:00:00 EDT 1997 · IEEE Transactions on Magnetics

DOI:https://doi.org/10.1109/20.617954· OSTI ID:561995

Spallas, J P; Mao, M; Law, B; Grabner, F; Cerjan, C ^[1]; O`Kane, D ^[2]

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1. Lawrence Livermore National Lab., CA (United States)
2. Read-Rite Corp., Fremont, CA (United States)

The authors have fabricated and tested GMR magnetic sensors that operate in the CPP mode. This work is a continuation of the ultra-high density magnetic sensor research introduced at INTERMAG 96f. They have made two significant modifications to the process sequence. First, contact to the sensor is made through a metal conduit deposited in situ with the multilayers. This deposition replaces electroplating. This configuration ensures a good electrical interface between the top of multilayer stack and the top contact, and a continuous, conductive current path to the sensor. The consequences of this modification are an increase in yield of operational devices to {ge}90% per wafer and a significant reduction of the device resistance to {le}560 m{Omega} and of the uniformity of the device resistance to {le}3%. Second, the as-deposited multilayer structure has been changed from [Cu 30 {angstrom}/Co 20 {angstrom}]{sub 18} (third peak) to [Cu 20.5 {angstrom}/Co 12 {angstrom}]{sub 30} (second peak) to increase the GMR response. The best second peak CPP GMR response from a single device is 39%. The sensitivity of that device is 0.13 %/Oe.

• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 561995
• Journal Information: IEEE Transactions on Magnetics, Journal Name: IEEE Transactions on Magnetics Journal Issue: 5Pt1 Vol. 33; ISSN IEMGAQ; ISSN 0018-9464
• Country of Publication: United States
• Language: English

Related Subjects

44 INSTRUMENTATION
INCLUDING NUCLEAR AND PARTICLE DETECTORS
COBALT ALLOYS
COPPER ALLOYS
FABRICATION
LAYERS
MAGNETIC PROBES
MAGNETORESISTANCE
PERFORMANCE
USES