Abstract
Dielectric properties of organic light-emitting diodes were investigated using ITO/Alq3/Al device. In spite of various advantages in organic light-emitting diodes, a fundamental study on physical properties is not yet sufficient. Dielectric properties are used for studying fundamental physical properties of materials through a frequency-dependent response. We have investigated magnitude and phase of impedance, electrical conductivity, and the dielectric loss depending on a bias-voltage variation using ITO/Alq3(60 nm)/Al device. The device shows a frequency-dependent response such that a major contribution is resistive below time constant and capacitive above time constant. Also, the device shows a voltage-dependent electrical conductivity in low-frequency region. A bulk resistance rapidly decreases as the frequency increases above 1 MHz. The dielectric loss shows that there appears an interfacial polarization in low-frequency region, and an orientational polarization in high-frequency region.
Original language | English |
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Pages (from-to) | 2626-2629 |
Number of pages | 4 |
Journal | Thin Solid Films |
Volume | 516 |
Issue number | 9 |
DOIs | |
Publication status | Published - 2008 Mar 3 |
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Surfaces and Interfaces
- Surfaces, Coatings and Films
- Metals and Alloys
- Materials Chemistry