Detail publikace

Near-field measurement of ZnS:Mn thin-film electroluminescent devices

GRMELA, L. KALA, J. TOMÁNEK, P.

Originální název

Near-field measurement of ZnS:Mn thin-film electroluminescent devices

Typ

článek ve sborníku ve WoS nebo Scopus

Jazyk

angličtina

Originální abstrakt

Thin film electroluminescent devices (TFELD) of inorganic phosphors have become of great interest since they offer a possible means of achieving a high-resolution, light-weight, compact video display panel for computer terminals or TV screens. Current inorganic TFEL phosphors are composed of II-VI wide bandgap semiconductor hosts (ZnS, SrS) which provide hot carriers (>2 eV) which impact excite luminescent centers (Mn, Tb, Ce, Cu). Sufficient hot carrier generation requires high field strengths (>1 MV/cm) exceeding the breakdown field of the phosphor thin film. An AC-biased dielectric/phosphor/dielectric layered structure allows reliable high field operation by current-limiting the electrical breakdown of the phosphor layer [1]. From a device point of view, a hysteresis in the brightness vs. applied voltage response curve is the most important advantage of AC-TFEL devices for large-area applications. In spite of the fact that the brightness of a memory-type EL is, in general, lower than that of non-memory ones, their advantage lies in the possibility of operating on an arbitary number of pixels in the matrix addressing mode at the same brightness level as the one-pixel device. Thus, memory devices are potentially more suitable for large area display operation [2]. To contribute to the local investigations of memory-type ZnS:Mn electroluminescent devices characteristics, we have been interested in the local electro-optical phenomena near the surfaces at the distances much less than the radiation wavelength. Beside a purely fundamental interest this is connected to the vigorous development of the scanning near-field optical microscopy. By scanning a 100 um x 100 um ACTFEL radiative surface in optical near-field we have found a pronounced hysteresis effect in the brightness vs. pulse width (B-W) response curve for memory-type ACTFEL devices driven near the threshold voltage. Moreover, we have investigated the dependence of the B-W characteristics on the ambient temperature and on the film thickness of the ZnS:Mn layer. The variations of the response times with respect to these parameters were also studied. The results will be reported in the paper.

Klíčová slova

ZnS:Mn thin film, near-field measurement, brightness, pulse width, ambient temperatue

Autoři

GRMELA, L.; KALA, J.; TOMÁNEK, P.

Vydáno

10. 9. 2006

Nakladatel

EPFL Lausanne

Místo

Lausanne, Switzerland

Strany od

326

Strany do

328

Strany počet

3

URL

http://www.nfo9.org

BibTex

@inproceedings{BUT19858,
  author="Lubomír {Grmela} and Jaroslav {Kala} and Pavel {Tománek}",
  title="Near-field measurement of ZnS:Mn thin-film electroluminescent devices",
  booktitle="Near-field optics, Nanophotonics and Related Techniques",
  year="2006",
  number="1",
  pages="326--328",
  publisher="EPFL Lausanne",
  address="Lausanne, Switzerland",
  url="http://www.nfo9.org"
}