AC Operation of GaN:Er Thin Film Electroluminescent Display Devices
Abstract
Thin-film electroluminescence has been obtained from GaN:Er deposited directly on amorphous dielectric layers. Electroluminescent device (ELD) structures consisting of a dielectric/GaN/dielectric were formed on p(+)-Si substrates. In contrast to previous GaN:Er ELDs which used epitaxial growth conditions on crystalline substrates and were operated under direct current (DC) bias, these ELDs were operated under an alternating (AC) bias. A maximum luminance value of 300, 60, and 15 cd/m(2) has been achieved from GaN:Er and AlGaN:Er AC-ELDs biased at 180 V and 100, 10, and 1 kHz, respectively. The emission spectra, which originate from Er(3+) 4frequency-4frequency transitions, consist of dominant visible emission at ~537/558 nm and infra-red (IR) emission at 1.5 micrometer. A violet emission peak at 415 nm indicates that hot carriers can gain up to ~3 eV energy for an applied voltage corresponding to 1.5 MV/cm applied field. The emitted intensity initially increases linearly with frequency, followed by a trend towards saturation. The frequency for 3 dB reduction from the linear relation is at ~65 kHz for visible emission and ~8 kHz for infrared emission. The saturation trends can be explained in terms of the spontaneous emission lifetimes of the visible (~10 microsecond) and IR (~1ms) Er(3+) emissions.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 2006
- Accession Number
- ADA448186
Entities
People
- A. J. Steckl
- J. Heikenfeld
Organizations
- University of Cincinnati