Magnetic media patterned by laser interference lithography

Rogelio Murillo Vallejo, R. Murillo Vallejo

    Abstract

    The scope of this thesis consists on the fabrication and magnetic characterization of CoNi/Pt and Co/Pt patterned films with perpendicular anisotropy with possible applications as an information storage medium. We have realized patterned magnetic nanodots arranged in square and hexagonal lattices with periodicites ranging from 600 nm down to 300 nm, which corresponds to bit densities from 1.8 Gb/sqi up to 7.2 Gb/sqi. The main aim has been focused towards the understanding of the problems involved in the fabrication of large samples (1 × 1 cm till 3 × 3 cm) and their write-ability. We discuss about the magnetic properties of an idealized magnetic pattern medium. Issues as the thermal stability, required magnetic anisotropy, bit to bit interaction and its consequences for the material’s switching field distribution are considered. Laser Interference Lithography has been the technique chosen to produce the patterned media samples studied in this work. A discussion about different photoresist stacks which were used in the course of this work is presented. We also discuss on the etching process and the photoresist removal afterwards. Regarding the magnetic analysis of the samples, three issues are mainly discussed: The possible damage to the magnetic properties of the material due to the fabrication process, in particular the ion beam etching step and the subsequent removal of the residual photoresist. The switching field distribution displayed by the samples and possible ways to reduce it are also discussed. Finally we examine the thermostability of our samples. Difficulties in writing and retrieving actual information are commented and possible lines for further research are sketched.
    Original languageUndefined
    Awarding Institution
    • University of Twente
    Supervisors/Advisors
    • Abelmann, Leon , Advisor
    • Supervisor
    • Lodder, J.C., Supervisor
    • Abelmann, L., Supervisor
    Sponsors
    Date of Award12 Apr 2006
    Place of PublicationEnschede
    Print ISBNs90-365-2344-3
    StatePublished - 12 Apr 2006

    Fingerprint

    photoresists
    thermal stability
    removal
    etching
    magnetic properties
    anisotropy
    fabrication
    theses
    lithography
    ion beams
    damage
    interference
    interactions

    Keywords

    • METIS-231289
    • EWI-8546
    • TST-LIL: Laser Interference Lithography
    • TST-SMI: Formerly in EWI-SMI
    • TST-uSPAM: micro Scanning Probe Array Memory
    • IR-55932

    Cite this

    Vallejo, R. M., & Murillo Vallejo, R. (2006). Magnetic media patterned by laser interference lithography Enschede
    Vallejo, Rogelio Murillo ; Murillo Vallejo, R.. / Magnetic media patterned by laser interference lithography. Enschede, 2006. 140 p.
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    abstract = "The scope of this thesis consists on the fabrication and magnetic characterization of CoNi/Pt and Co/Pt patterned films with perpendicular anisotropy with possible applications as an information storage medium. We have realized patterned magnetic nanodots arranged in square and hexagonal lattices with periodicites ranging from 600 nm down to 300 nm, which corresponds to bit densities from 1.8 Gb/sqi up to 7.2 Gb/sqi. The main aim has been focused towards the understanding of the problems involved in the fabrication of large samples (1 × 1 cm till 3 × 3 cm) and their write-ability. We discuss about the magnetic properties of an idealized magnetic pattern medium. Issues as the thermal stability, required magnetic anisotropy, bit to bit interaction and its consequences for the material’s switching field distribution are considered. Laser Interference Lithography has been the technique chosen to produce the patterned media samples studied in this work. A discussion about different photoresist stacks which were used in the course of this work is presented. We also discuss on the etching process and the photoresist removal afterwards. Regarding the magnetic analysis of the samples, three issues are mainly discussed: The possible damage to the magnetic properties of the material due to the fabrication process, in particular the ion beam etching step and the subsequent removal of the residual photoresist. The switching field distribution displayed by the samples and possible ways to reduce it are also discussed. Finally we examine the thermostability of our samples. Difficulties in writing and retrieving actual information are commented and possible lines for further research are sketched.",
    keywords = "METIS-231289, EWI-8546, TST-LIL: Laser Interference Lithography, TST-SMI: Formerly in EWI-SMI, TST-uSPAM: micro Scanning Probe Array Memory, IR-55932",
    author = "Vallejo, {Rogelio Murillo} and {Murillo Vallejo}, R.",
    year = "2006",
    month = "4",
    isbn = "90-365-2344-3",
    school = "University of Twente",

    }

    Vallejo, RM & Murillo Vallejo, R 2006, 'Magnetic media patterned by laser interference lithography', University of Twente, Enschede.

    Magnetic media patterned by laser interference lithography. / Vallejo, Rogelio Murillo; Murillo Vallejo, R.

    Enschede, 2006. 140 p.

    Research output: ScientificPhD Thesis - Research UT, graduation UT

    TY - THES

    T1 - Magnetic media patterned by laser interference lithography

    AU - Vallejo,Rogelio Murillo

    AU - Murillo Vallejo,R.

    PY - 2006/4/12

    Y1 - 2006/4/12

    N2 - The scope of this thesis consists on the fabrication and magnetic characterization of CoNi/Pt and Co/Pt patterned films with perpendicular anisotropy with possible applications as an information storage medium. We have realized patterned magnetic nanodots arranged in square and hexagonal lattices with periodicites ranging from 600 nm down to 300 nm, which corresponds to bit densities from 1.8 Gb/sqi up to 7.2 Gb/sqi. The main aim has been focused towards the understanding of the problems involved in the fabrication of large samples (1 × 1 cm till 3 × 3 cm) and their write-ability. We discuss about the magnetic properties of an idealized magnetic pattern medium. Issues as the thermal stability, required magnetic anisotropy, bit to bit interaction and its consequences for the material’s switching field distribution are considered. Laser Interference Lithography has been the technique chosen to produce the patterned media samples studied in this work. A discussion about different photoresist stacks which were used in the course of this work is presented. We also discuss on the etching process and the photoresist removal afterwards. Regarding the magnetic analysis of the samples, three issues are mainly discussed: The possible damage to the magnetic properties of the material due to the fabrication process, in particular the ion beam etching step and the subsequent removal of the residual photoresist. The switching field distribution displayed by the samples and possible ways to reduce it are also discussed. Finally we examine the thermostability of our samples. Difficulties in writing and retrieving actual information are commented and possible lines for further research are sketched.

    AB - The scope of this thesis consists on the fabrication and magnetic characterization of CoNi/Pt and Co/Pt patterned films with perpendicular anisotropy with possible applications as an information storage medium. We have realized patterned magnetic nanodots arranged in square and hexagonal lattices with periodicites ranging from 600 nm down to 300 nm, which corresponds to bit densities from 1.8 Gb/sqi up to 7.2 Gb/sqi. The main aim has been focused towards the understanding of the problems involved in the fabrication of large samples (1 × 1 cm till 3 × 3 cm) and their write-ability. We discuss about the magnetic properties of an idealized magnetic pattern medium. Issues as the thermal stability, required magnetic anisotropy, bit to bit interaction and its consequences for the material’s switching field distribution are considered. Laser Interference Lithography has been the technique chosen to produce the patterned media samples studied in this work. A discussion about different photoresist stacks which were used in the course of this work is presented. We also discuss on the etching process and the photoresist removal afterwards. Regarding the magnetic analysis of the samples, three issues are mainly discussed: The possible damage to the magnetic properties of the material due to the fabrication process, in particular the ion beam etching step and the subsequent removal of the residual photoresist. The switching field distribution displayed by the samples and possible ways to reduce it are also discussed. Finally we examine the thermostability of our samples. Difficulties in writing and retrieving actual information are commented and possible lines for further research are sketched.

    KW - METIS-231289

    KW - EWI-8546

    KW - TST-LIL: Laser Interference Lithography

    KW - TST-SMI: Formerly in EWI-SMI

    KW - TST-uSPAM: micro Scanning Probe Array Memory

    KW - IR-55932

    M3 - PhD Thesis - Research UT, graduation UT

    SN - 90-365-2344-3

    ER -

    Vallejo RM, Murillo Vallejo R. Magnetic media patterned by laser interference lithography. Enschede, 2006. 140 p.