Effects of Ultraviolet Photon Irradiation on the Dielectric Properties of Polyimide

Akira Yamaguchi, Yoshimichi Ohki

    Research output: Contribution to journalArticle

    2 Citations (Scopus)

    Abstract

    Ultraviolet photons were irradiated to the surface of all-aromatic polyimide films using a KrF excimer laser or a KrCl excimer lamp, and electrical properties such as permittivity, dielectric loss factor, conductivity, and space charge distribution were measured. In the case of the intense laser irradiation, the photo-induced change is drastic. The irradiated side of the sample is carbonized and becomes conductive. The apparent thickness of the remaining insulating region estimated by the space charge distribution measurements agrees with that observed by an optical microscope. The permittivity of the remaining apparently insulating region decreases as the irradiation proceeds, which is due to a decrease in the number of carbonyl groups. The dielectric loss factor and conductivity in this region increase since the leakage current increases even in this apparently insulating region. The activation energy of conduction also increases. In the case of the weak lamp irradiation, the permittivity decreases and the conductivity increases, although clear surface change is hardly observable. It is indicated from space charge distribution measurements that carrier traps are formed by the irradiation.

    Original languageEnglish
    Pages (from-to)98-103
    Number of pages6
    JournalIEEJ Transactions on Fundamentals and Materials
    Volume124
    Issue number1
    DOIs
    Publication statusPublished - 2004

    Fingerprint

    Charge distribution
    Electric space charge
    Polyimides
    Dielectric properties
    Permittivity
    Photons
    Irradiation
    Dielectric losses
    Electric lamps
    Excimer lasers
    Laser beam effects
    Leakage currents
    Electric properties
    Microscopes
    Activation energy

    Keywords

    • conductivity
    • permittivity
    • polyimide
    • space charge
    • ultraviolet rays

    ASJC Scopus subject areas

    • Electrical and Electronic Engineering

    Cite this

    Effects of Ultraviolet Photon Irradiation on the Dielectric Properties of Polyimide. / Yamaguchi, Akira; Ohki, Yoshimichi.

    In: IEEJ Transactions on Fundamentals and Materials, Vol. 124, No. 1, 2004, p. 98-103.

    Research output: Contribution to journalArticle

    @article{65ad76cf106b43c3afc785405a37a96c,
    title = "Effects of Ultraviolet Photon Irradiation on the Dielectric Properties of Polyimide",
    abstract = "Ultraviolet photons were irradiated to the surface of all-aromatic polyimide films using a KrF excimer laser or a KrCl excimer lamp, and electrical properties such as permittivity, dielectric loss factor, conductivity, and space charge distribution were measured. In the case of the intense laser irradiation, the photo-induced change is drastic. The irradiated side of the sample is carbonized and becomes conductive. The apparent thickness of the remaining insulating region estimated by the space charge distribution measurements agrees with that observed by an optical microscope. The permittivity of the remaining apparently insulating region decreases as the irradiation proceeds, which is due to a decrease in the number of carbonyl groups. The dielectric loss factor and conductivity in this region increase since the leakage current increases even in this apparently insulating region. The activation energy of conduction also increases. In the case of the weak lamp irradiation, the permittivity decreases and the conductivity increases, although clear surface change is hardly observable. It is indicated from space charge distribution measurements that carrier traps are formed by the irradiation.",
    keywords = "conductivity, permittivity, polyimide, space charge, ultraviolet rays",
    author = "Akira Yamaguchi and Yoshimichi Ohki",
    year = "2004",
    doi = "10.1541/ieejfms.124.98",
    language = "English",
    volume = "124",
    pages = "98--103",
    journal = "IEEJ Transactions on Fundamentals and Materials",
    issn = "0385-4205",
    publisher = "The Institute of Electrical Engineers of Japan",
    number = "1",

    }

    TY - JOUR

    T1 - Effects of Ultraviolet Photon Irradiation on the Dielectric Properties of Polyimide

    AU - Yamaguchi, Akira

    AU - Ohki, Yoshimichi

    PY - 2004

    Y1 - 2004

    N2 - Ultraviolet photons were irradiated to the surface of all-aromatic polyimide films using a KrF excimer laser or a KrCl excimer lamp, and electrical properties such as permittivity, dielectric loss factor, conductivity, and space charge distribution were measured. In the case of the intense laser irradiation, the photo-induced change is drastic. The irradiated side of the sample is carbonized and becomes conductive. The apparent thickness of the remaining insulating region estimated by the space charge distribution measurements agrees with that observed by an optical microscope. The permittivity of the remaining apparently insulating region decreases as the irradiation proceeds, which is due to a decrease in the number of carbonyl groups. The dielectric loss factor and conductivity in this region increase since the leakage current increases even in this apparently insulating region. The activation energy of conduction also increases. In the case of the weak lamp irradiation, the permittivity decreases and the conductivity increases, although clear surface change is hardly observable. It is indicated from space charge distribution measurements that carrier traps are formed by the irradiation.

    AB - Ultraviolet photons were irradiated to the surface of all-aromatic polyimide films using a KrF excimer laser or a KrCl excimer lamp, and electrical properties such as permittivity, dielectric loss factor, conductivity, and space charge distribution were measured. In the case of the intense laser irradiation, the photo-induced change is drastic. The irradiated side of the sample is carbonized and becomes conductive. The apparent thickness of the remaining insulating region estimated by the space charge distribution measurements agrees with that observed by an optical microscope. The permittivity of the remaining apparently insulating region decreases as the irradiation proceeds, which is due to a decrease in the number of carbonyl groups. The dielectric loss factor and conductivity in this region increase since the leakage current increases even in this apparently insulating region. The activation energy of conduction also increases. In the case of the weak lamp irradiation, the permittivity decreases and the conductivity increases, although clear surface change is hardly observable. It is indicated from space charge distribution measurements that carrier traps are formed by the irradiation.

    KW - conductivity

    KW - permittivity

    KW - polyimide

    KW - space charge

    KW - ultraviolet rays

    UR - http://www.scopus.com/inward/record.url?scp=85009627908&partnerID=8YFLogxK

    UR - http://www.scopus.com/inward/citedby.url?scp=85009627908&partnerID=8YFLogxK

    U2 - 10.1541/ieejfms.124.98

    DO - 10.1541/ieejfms.124.98

    M3 - Article

    AN - SCOPUS:85009627908

    VL - 124

    SP - 98

    EP - 103

    JO - IEEJ Transactions on Fundamentals and Materials

    JF - IEEJ Transactions on Fundamentals and Materials

    SN - 0385-4205

    IS - 1

    ER -